contrib/tcpdump/tcpdump.c

   1 /*
   2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
   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: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  *
  21  * Support for splitting captures into multiple files with a maximum
  22  * file size:
  23  *
  24  * Copyright (c) 2001
  25  *      Seth Webster <swebster@sst.ll.mit.edu>
  26  */
  27
  28 #ifndef lint
  29 static const char copyright[] _U_ =
  30     "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
  31 The Regents of the University of California.  All rights reserved.\n";
  32 #endif
  33
  34 /*
  35  * tcpdump - dump traffic on a network
  36  *
  37  * First written in 1987 by Van Jacobson, Lawrence Berkeley Laboratory.
  38  * Mercilessly hacked and occasionally improved since then via the
  39  * combined efforts of Van, Steve McCanne and Craig Leres of LBL.
  40  */
  41
  42 #ifdef HAVE_CONFIG_H
  43 #include "config.h"
  44 #endif
  45
  46 /*
  47  * Mac OS X may ship pcap.h from libpcap 0.6 with a libpcap based on
  48  * 0.8.  That means it has pcap_findalldevs() but the header doesn't
  49  * define pcap_if_t, meaning that we can't actually *use* pcap_findalldevs().
  50  */
  51 #ifdef HAVE_PCAP_FINDALLDEVS
  52 #ifndef HAVE_PCAP_IF_T
  53 #undef HAVE_PCAP_FINDALLDEVS
  54 #endif
  55 #endif
  56
  57 #include <netdissect-stdinc.h>
  58
  59 #include <sys/stat.h>
  60
  61 #ifdef HAVE_FCNTL_H
  62 #include <fcntl.h>
  63 #endif
  64
  65 #ifdef HAVE_LIBCRYPTO
  66 #include <openssl/crypto.h>
  67 #endif
  68
  69 #ifdef HAVE_GETOPT_LONG
  70 #include <getopt.h>
  71 #else
  72 #include "getopt_long.h"
  73 #endif
  74 /* Capsicum-specific code requires macros from <net/bpf.h>, which will fail
  75  * to compile if <pcap.h> has already been included; including the headers
  76  * in the opposite order works fine.
  77  */
  78 #ifdef HAVE_CAPSICUM
  79 #include <sys/capsicum.h>
  80 #include <sys/sysctl.h>
  81 #include <sys/nv.h>
  82 #include <sys/ioccom.h>
  83 #include <net/bpf.h>
  84 #include <libgen.h>
  85 #ifdef HAVE_CASPER
  86 #include <libcasper.h>
  87 #include <casper/cap_dns.h>
  88 #endif  /* HAVE_CASPER */
  89 #endif  /* HAVE_CAPSICUM */
  90 #include <pcap.h>
  91 #include <signal.h>
  92 #include <stdio.h>
  93 #include <stdarg.h>
  94 #include <stdlib.h>
  95 #include <string.h>
  96 #include <limits.h>
  97 #ifndef _WIN32
  98 #include <sys/wait.h>
  99 #include <sys/resource.h>
 100 #include <pwd.h>
 101 #include <grp.h>
 102 #endif /* _WIN32 */
 103
 104 /* capabilities convenience library */
 105 /* If a code depends on HAVE_LIBCAP_NG, it depends also on HAVE_CAP_NG_H.
 106  * If HAVE_CAP_NG_H is not defined, undefine HAVE_LIBCAP_NG.
 107  * Thus, the later tests are done only on HAVE_LIBCAP_NG.
 108  */
 109 #ifdef HAVE_LIBCAP_NG
 110 #ifdef HAVE_CAP_NG_H
 111 #include <cap-ng.h>
 112 #else
 113 #undef HAVE_LIBCAP_NG
 114 #endif /* HAVE_CAP_NG_H */
 115 #endif /* HAVE_LIBCAP_NG */
 116
 117 #include "netdissect.h"
 118 #include "interface.h"
 119 #include "addrtoname.h"
 120 #include "machdep.h"
 121 #include "setsignal.h"
 122 #include "gmt2local.h"
 123 #include "pcap-missing.h"
 124 #include "ascii_strcasecmp.h"
 125
 126 #include "print.h"
 127
 128 #ifndef PATH_MAX
 129 #define PATH_MAX 1024
 130 #endif
 131
 132 #ifdef SIGINFO
 133 #define SIGNAL_REQ_INFO SIGINFO
 134 #elif SIGUSR1
 135 #define SIGNAL_REQ_INFO SIGUSR1
 136 #endif
 137
 138 static int Bflag;                       /* buffer size */
 139 static int Cflag;                       /* rotate dump files after this many bytes */
 140 static int Cflag_count;                 /* Keep track of which file number we're writing */
 141 static int Dflag;                       /* list available devices and exit */
 142 /*
 143  * This is exported because, in some versions of libpcap, if libpcap
 144  * is built with optimizer debugging code (which is *NOT* the default
 145  * configuration!), the library *imports*(!) a variable named dflag,
 146  * under the expectation that tcpdump is exporting it, to govern
 147  * how much debugging information to print when optimizing
 148  * the generated BPF code.
 149  *
 150  * This is a horrible hack; newer versions of libpcap don't import
 151  * dflag but, instead, *if* built with optimizer debugging code,
 152  * *export* a routine to set that flag.
 153  */
 154 int dflag;                              /* print filter code */
 155 static int Gflag;                       /* rotate dump files after this many seconds */
 156 static int Gflag_count;                 /* number of files created with Gflag rotation */
 157 static time_t Gflag_time;               /* The last time_t the dump file was rotated. */
 158 static int Lflag;                       /* list available data link types and exit */
 159 static int Iflag;                       /* rfmon (monitor) mode */
 160 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
 161 static int Jflag;                       /* list available time stamp types */
 162 #endif
 163 static int jflag = -1;                  /* packet time stamp source */
 164 static int pflag;                       /* don't go promiscuous */
 165 #ifdef HAVE_PCAP_SETDIRECTION
 166 static int Qflag = -1;                  /* restrict captured packet by send/receive direction */
 167 #endif
 168 static int Uflag;                       /* "unbuffered" output of dump files */
 169 static int Wflag;                       /* recycle output files after this number of files */
 170 static int WflagChars;
 171 static char *zflag = NULL;              /* compress each savefile using a specified command (like gzip or bzip2) */
 172 static int immediate_mode;
 173
 174 static int infodelay;
 175 static int infoprint;
 176
 177 char *program_name;
 178
 179 #ifdef HAVE_CASPER
 180 cap_channel_t *capdns;
 181 #endif
 182
 183 /* Forwards */
 184 static void error(const char *, ...)
 185      __attribute__((noreturn))
 186 #ifdef __ATTRIBUTE___FORMAT_OK
 187      __attribute__((format (printf, 1, 2)))
 188 #endif /* __ATTRIBUTE___FORMAT_OK */
 189      ;
 190 static void warning(const char *, ...)
 191 #ifdef __ATTRIBUTE___FORMAT_OK
 192      __attribute__((format (printf, 1, 2)))
 193 #endif /* __ATTRIBUTE___FORMAT_OK */
 194      ;
 195 static void exit_tcpdump(int) __attribute__((noreturn));
 196 static RETSIGTYPE cleanup(int);
 197 static RETSIGTYPE child_cleanup(int);
 198 static void print_version(void);
 199 static void print_usage(void);
 200 static void show_tstamp_types_and_exit(pcap_t *, const char *device) __attribute__((noreturn));
 201 static void show_dlts_and_exit(pcap_t *, const char *device) __attribute__((noreturn));
 202 #ifdef HAVE_PCAP_FINDALLDEVS
 203 static void show_devices_and_exit (void) __attribute__((noreturn));
 204 #endif
 205
 206 static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
 207 static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *);
 208 static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
 209 static void droproot(const char *, const char *);
 210
 211 #ifdef SIGNAL_REQ_INFO
 212 RETSIGTYPE requestinfo(int);
 213 #endif
 214
 215 #if defined(USE_WIN32_MM_TIMER)
 216   #include <MMsystem.h>
 217   static UINT timer_id;
 218   static void CALLBACK verbose_stats_dump(UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR);
 219 #elif defined(HAVE_ALARM)
 220   static void verbose_stats_dump(int sig);
 221 #endif
 222
 223 static void info(int);
 224 static u_int packets_captured;
 225
 226 #ifdef HAVE_PCAP_FINDALLDEVS
 227 static const struct tok status_flags[] = {
 228 #ifdef PCAP_IF_UP
 229         { PCAP_IF_UP,       "Up"       },
 230 #endif
 231 #ifdef PCAP_IF_RUNNING
 232         { PCAP_IF_RUNNING,  "Running"  },
 233 #endif
 234         { PCAP_IF_LOOPBACK, "Loopback" },
 235         { 0, NULL }
 236 };
 237 #endif
 238
 239 static pcap_t *pd;
 240
 241 static int supports_monitor_mode;
 242
 243 extern int optind;
 244 extern int opterr;
 245 extern char *optarg;
 246
 247 struct dump_info {
 248         char    *WFileName;
 249         char    *CurrentFileName;
 250         pcap_t  *pd;
 251         pcap_dumper_t *p;
 252 #ifdef HAVE_CAPSICUM
 253         int     dirfd;
 254 #endif
 255 };
 256
 257 #if defined(HAVE_PCAP_SET_PARSER_DEBUG)
 258 /*
 259  * We have pcap_set_parser_debug() in libpcap; declare it (it's not declared
 260  * by any libpcap header, because it's a special hack, only available if
 261  * libpcap was configured to include it, and only intended for use by
 262  * libpcap developers trying to debug the parser for filter expressions).
 263  */
 264 #ifdef _WIN32
 265 __declspec(dllimport)
 266 #else /* _WIN32 */
 267 extern
 268 #endif /* _WIN32 */
 269 void pcap_set_parser_debug(int);
 270 #elif defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
 271 /*
 272  * We don't have pcap_set_parser_debug() in libpcap, but we do have
 273  * pcap_debug or yydebug.  Make a local version of pcap_set_parser_debug()
 274  * to set the flag, and define HAVE_PCAP_SET_PARSER_DEBUG.
 275  */
 276 static void
 277 pcap_set_parser_debug(int value)
 278 {
 279 #ifdef HAVE_PCAP_DEBUG
 280         extern int pcap_debug;
 281
 282         pcap_debug = value;
 283 #else /* HAVE_PCAP_DEBUG */
 284         extern int yydebug;
 285
 286         yydebug = value;
 287 #endif /* HAVE_PCAP_DEBUG */
 288 }
 289
 290 #define HAVE_PCAP_SET_PARSER_DEBUG
 291 #endif
 292
 293 #if defined(HAVE_PCAP_SET_OPTIMIZER_DEBUG)
 294 /*
 295  * We have pcap_set_optimizer_debug() in libpcap; declare it (it's not declared
 296  * by any libpcap header, because it's a special hack, only available if
 297  * libpcap was configured to include it, and only intended for use by
 298  * libpcap developers trying to debug the optimizer for filter expressions).
 299  */
 300 #ifdef _WIN32
 301 __declspec(dllimport)
 302 #else /* _WIN32 */
 303 extern
 304 #endif /* _WIN32 */
 305 void pcap_set_optimizer_debug(int);
 306 #endif
 307
 308 /* VARARGS */
 309 static void
 310 error(const char *fmt, ...)
 311 {
 312         va_list ap;
 313
 314         (void)fprintf(stderr, "%s: ", program_name);
 315         va_start(ap, fmt);
 316         (void)vfprintf(stderr, fmt, ap);
 317         va_end(ap);
 318         if (*fmt) {
 319                 fmt += strlen(fmt);
 320                 if (fmt[-1] != '\n')
 321                         (void)fputc('\n', stderr);
 322         }
 323         exit_tcpdump(1);
 324         /* NOTREACHED */
 325 }
 326
 327 /* VARARGS */
 328 static void
 329 warning(const char *fmt, ...)
 330 {
 331         va_list ap;
 332
 333         (void)fprintf(stderr, "%s: WARNING: ", program_name);
 334         va_start(ap, fmt);
 335         (void)vfprintf(stderr, fmt, ap);
 336         va_end(ap);
 337         if (*fmt) {
 338                 fmt += strlen(fmt);
 339                 if (fmt[-1] != '\n')
 340                         (void)fputc('\n', stderr);
 341         }
 342 }
 343
 344 static void
 345 exit_tcpdump(int status)
 346 {
 347         nd_cleanup();
 348         exit(status);
 349 }
 350
 351 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
 352 static void
 353 show_tstamp_types_and_exit(pcap_t *pc, const char *device)
 354 {
 355         int n_tstamp_types;
 356         int *tstamp_types = 0;
 357         const char *tstamp_type_name;
 358         int i;
 359
 360         n_tstamp_types = pcap_list_tstamp_types(pc, &tstamp_types);
 361         if (n_tstamp_types < 0)
 362                 error("%s", pcap_geterr(pc));
 363
 364         if (n_tstamp_types == 0) {
 365                 fprintf(stderr, "Time stamp type cannot be set for %s\n",
 366                     device);
 367                 exit_tcpdump(0);
 368         }
 369         fprintf(stderr, "Time stamp types for %s (use option -j to set):\n",
 370             device);
 371         for (i = 0; i < n_tstamp_types; i++) {
 372                 tstamp_type_name = pcap_tstamp_type_val_to_name(tstamp_types[i]);
 373                 if (tstamp_type_name != NULL) {
 374                         (void) fprintf(stderr, "  %s (%s)\n", tstamp_type_name,
 375                             pcap_tstamp_type_val_to_description(tstamp_types[i]));
 376                 } else {
 377                         (void) fprintf(stderr, "  %d\n", tstamp_types[i]);
 378                 }
 379         }
 380         pcap_free_tstamp_types(tstamp_types);
 381         exit_tcpdump(0);
 382 }
 383 #endif
 384
 385 static void
 386 show_dlts_and_exit(pcap_t *pc, const char *device)
 387 {
 388         int n_dlts, i;
 389         int *dlts = 0;
 390         const char *dlt_name;
 391
 392         n_dlts = pcap_list_datalinks(pc, &dlts);
 393         if (n_dlts < 0)
 394                 error("%s", pcap_geterr(pc));
 395         else if (n_dlts == 0 || !dlts)
 396                 error("No data link types.");
 397
 398         /*
 399          * If the interface is known to support monitor mode, indicate
 400          * whether these are the data link types available when not in
 401          * monitor mode, if -I wasn't specified, or when in monitor mode,
 402          * when -I was specified (the link-layer types available in
 403          * monitor mode might be different from the ones available when
 404          * not in monitor mode).
 405          */
 406         if (supports_monitor_mode)
 407                 (void) fprintf(stderr, "Data link types for %s %s (use option -y to set):\n",
 408                     device,
 409                     Iflag ? "when in monitor mode" : "when not in monitor mode");
 410         else
 411                 (void) fprintf(stderr, "Data link types for %s (use option -y to set):\n",
 412                     device);
 413
 414         for (i = 0; i < n_dlts; i++) {
 415                 dlt_name = pcap_datalink_val_to_name(dlts[i]);
 416                 if (dlt_name != NULL) {
 417                         (void) fprintf(stderr, "  %s (%s)", dlt_name,
 418                             pcap_datalink_val_to_description(dlts[i]));
 419
 420                         /*
 421                          * OK, does tcpdump handle that type?
 422                          */
 423                         if (!has_printer(dlts[i]))
 424                                 (void) fprintf(stderr, " (printing not supported)");
 425                         fprintf(stderr, "\n");
 426                 } else {
 427                         (void) fprintf(stderr, "  DLT %d (printing not supported)\n",
 428                             dlts[i]);
 429                 }
 430         }
 431 #ifdef HAVE_PCAP_FREE_DATALINKS
 432         pcap_free_datalinks(dlts);
 433 #endif
 434         exit_tcpdump(0);
 435 }
 436
 437 #ifdef HAVE_PCAP_FINDALLDEVS
 438 static void
 439 show_devices_and_exit (void)
 440 {
 441         pcap_if_t *dev, *devlist;
 442         char ebuf[PCAP_ERRBUF_SIZE];
 443         int i;
 444
 445         if (pcap_findalldevs(&devlist, ebuf) < 0)
 446                 error("%s", ebuf);
 447         for (i = 0, dev = devlist; dev != NULL; i++, dev = dev->next) {
 448                 printf("%d.%s", i+1, dev->name);
 449                 if (dev->description != NULL)
 450                         printf(" (%s)", dev->description);
 451                 if (dev->flags != 0)
 452                         printf(" [%s]", bittok2str(status_flags, "none", dev->flags));
 453                 printf("\n");
 454         }
 455         pcap_freealldevs(devlist);
 456         exit_tcpdump(0);
 457 }
 458 #endif /* HAVE_PCAP_FINDALLDEVS */
 459
 460 /*
 461  * Short options.
 462  *
 463  * Note that there we use all letters for short options except for g, k,
 464  * o, and P, and those are used by other versions of tcpdump, and we should
 465  * only use them for the same purposes that the other versions of tcpdump
 466  * use them:
 467  *
 468  * OS X tcpdump uses -g to force non--v output for IP to be on one
 469  * line, making it more "g"repable;
 470  *
 471  * OS X tcpdump uses -k to specify that packet comments in pcap-ng files
 472  * should be printed;
 473  *
 474  * OpenBSD tcpdump uses -o to indicate that OS fingerprinting should be done
 475  * for hosts sending TCP SYN packets;
 476  *
 477  * OS X tcpdump uses -P to indicate that -w should write pcap-ng rather
 478  * than pcap files.
 479  *
 480  * OS X tcpdump also uses -Q to specify expressions that match packet
 481  * metadata, including but not limited to the packet direction.
 482  * The expression syntax is different from a simple "in|out|inout",
 483  * and those expressions aren't accepted by OS X tcpdump, but the
 484  * equivalents would be "in" = "dir=in", "out" = "dir=out", and
 485  * "inout" = "dir=in or dir=out", and the parser could conceivably
 486  * special-case "in", "out", and "inout" as expressions for backwards
 487  * compatibility, so all is not (yet) lost.
 488  */
 489
 490 /*
 491  * Set up flags that might or might not be supported depending on the
 492  * version of libpcap we're using.
 493  */
 494 #if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
 495 #define B_FLAG          "B:"
 496 #define B_FLAG_USAGE    " [ -B size ]"
 497 #else /* defined(HAVE_PCAP_CREATE) || defined(_WIN32) */
 498 #define B_FLAG
 499 #define B_FLAG_USAGE
 500 #endif /* defined(HAVE_PCAP_CREATE) || defined(_WIN32) */
 501
 502 #ifdef HAVE_PCAP_CREATE
 503 #define I_FLAG          "I"
 504 #else /* HAVE_PCAP_CREATE */
 505 #define I_FLAG
 506 #endif /* HAVE_PCAP_CREATE */
 507
 508 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
 509 #define j_FLAG          "j:"
 510 #define j_FLAG_USAGE    " [ -j tstamptype ]"
 511 #define J_FLAG          "J"
 512 #else /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
 513 #define j_FLAG
 514 #define j_FLAG_USAGE
 515 #define J_FLAG
 516 #endif /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
 517
 518 #ifdef HAVE_PCAP_FINDALLDEVS
 519 #define D_FLAG  "D"
 520 #else
 521 #define D_FLAG
 522 #endif
 523
 524 #ifdef HAVE_PCAP_DUMP_FLUSH
 525 #define U_FLAG  "U"
 526 #else
 527 #define U_FLAG
 528 #endif
 529
 530 #ifdef HAVE_PCAP_SETDIRECTION
 531 #define Q_FLAG "Q:"
 532 #else
 533 #define Q_FLAG
 534 #endif
 535
 536 #define SHORTOPTS "aAb" B_FLAG "c:C:d" D_FLAG "eE:fF:G:hHi:" I_FLAG j_FLAG J_FLAG "KlLm:M:nNOpq" Q_FLAG "r:s:StT:u" U_FLAG "vV:w:W:xXy:Yz:Z:#"
 537
 538 /*
 539  * Long options.
 540  *
 541  * We do not currently have long options corresponding to all short
 542  * options; we should probably pick appropriate option names for them.
 543  *
 544  * However, the short options where the number of times the option is
 545  * specified matters, such as -v and -d and -t, should probably not
 546  * just map to a long option, as saying
 547  *
 548  *  tcpdump --verbose --verbose
 549  *
 550  * doesn't make sense; it should be --verbosity={N} or something such
 551  * as that.
 552  *
 553  * For long options with no corresponding short options, we define values
 554  * outside the range of ASCII graphic characters, make that the last
 555  * component of the entry for the long option, and have a case for that
 556  * option in the switch statement.
 557  */
 558 #define OPTION_VERSION          128
 559 #define OPTION_TSTAMP_PRECISION 129
 560 #define OPTION_IMMEDIATE_MODE   130
 561
 562 static const struct option longopts[] = {
 563 #if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
 564         { "buffer-size", required_argument, NULL, 'B' },
 565 #endif
 566         { "list-interfaces", no_argument, NULL, 'D' },
 567         { "help", no_argument, NULL, 'h' },
 568         { "interface", required_argument, NULL, 'i' },
 569 #ifdef HAVE_PCAP_CREATE
 570         { "monitor-mode", no_argument, NULL, 'I' },
 571 #endif
 572 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
 573         { "time-stamp-type", required_argument, NULL, 'j' },
 574         { "list-time-stamp-types", no_argument, NULL, 'J' },
 575 #endif
 576 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
 577         { "time-stamp-precision", required_argument, NULL, OPTION_TSTAMP_PRECISION},
 578 #endif
 579         { "dont-verify-checksums", no_argument, NULL, 'K' },
 580         { "list-data-link-types", no_argument, NULL, 'L' },
 581         { "no-optimize", no_argument, NULL, 'O' },
 582         { "no-promiscuous-mode", no_argument, NULL, 'p' },
 583 #ifdef HAVE_PCAP_SETDIRECTION
 584         { "direction", required_argument, NULL, 'Q' },
 585 #endif
 586         { "snapshot-length", required_argument, NULL, 's' },
 587         { "absolute-tcp-sequence-numbers", no_argument, NULL, 'S' },
 588 #ifdef HAVE_PCAP_DUMP_FLUSH
 589         { "packet-buffered", no_argument, NULL, 'U' },
 590 #endif
 591         { "linktype", required_argument, NULL, 'y' },
 592 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
 593         { "immediate-mode", no_argument, NULL, OPTION_IMMEDIATE_MODE },
 594 #endif
 595 #ifdef HAVE_PCAP_SET_PARSER_DEBUG
 596         { "debug-filter-parser", no_argument, NULL, 'Y' },
 597 #endif
 598         { "relinquish-privileges", required_argument, NULL, 'Z' },
 599         { "number", no_argument, NULL, '#' },
 600         { "version", no_argument, NULL, OPTION_VERSION },
 601         { NULL, 0, NULL, 0 }
 602 };
 603
 604 #ifndef _WIN32
 605 /* Drop root privileges and chroot if necessary */
 606 static void
 607 droproot(const char *username, const char *chroot_dir)
 608 {
 609         struct passwd *pw = NULL;
 610
 611         if (chroot_dir && !username) {
 612                 fprintf(stderr, "%s: Chroot without dropping root is insecure\n",
 613                         program_name);
 614                 exit_tcpdump(1);
 615         }
 616
 617         pw = getpwnam(username);
 618         if (pw) {
 619                 if (chroot_dir) {
 620                         if (chroot(chroot_dir) != 0 || chdir ("/") != 0) {
 621                                 fprintf(stderr, "%s: Couldn't chroot/chdir to '%.64s': %s\n",
 622                                         program_name, chroot_dir, pcap_strerror(errno));
 623                                 exit_tcpdump(1);
 624                         }
 625                 }
 626 #ifdef HAVE_LIBCAP_NG
 627                 {
 628                         int ret = capng_change_id(pw->pw_uid, pw->pw_gid, CAPNG_NO_FLAG);
 629                         if (ret < 0) {
 630                                 fprintf(stderr, "error : ret %d\n", ret);
 631                         } else {
 632                                 fprintf(stderr, "dropped privs to %s\n", username);
 633                         }
 634                 }
 635 #else
 636                 if (initgroups(pw->pw_name, pw->pw_gid) != 0 ||
 637                     setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) {
 638                         fprintf(stderr, "%s: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n",
 639                                 program_name, username,
 640                                 (unsigned long)pw->pw_uid,
 641                                 (unsigned long)pw->pw_gid,
 642                                 pcap_strerror(errno));
 643                         exit_tcpdump(1);
 644                 }
 645                 else {
 646                         fprintf(stderr, "dropped privs to %s\n", username);
 647                 }
 648 #endif /* HAVE_LIBCAP_NG */
 649         }
 650         else {
 651                 fprintf(stderr, "%s: Couldn't find user '%.32s'\n",
 652                         program_name, username);
 653                 exit_tcpdump(1);
 654         }
 655 #ifdef HAVE_LIBCAP_NG
 656         /* We don't need CAP_SETUID, CAP_SETGID and CAP_SYS_CHROOT any more. */
 657         capng_updatev(
 658                 CAPNG_DROP,
 659                 CAPNG_EFFECTIVE | CAPNG_PERMITTED,
 660                 CAP_SETUID,
 661                 CAP_SETGID,
 662                 CAP_SYS_CHROOT,
 663                 -1);
 664         capng_apply(CAPNG_SELECT_BOTH);
 665 #endif /* HAVE_LIBCAP_NG */
 666
 667 }
 668 #endif /* _WIN32 */
 669
 670 static int
 671 getWflagChars(int x)
 672 {
 673         int c = 0;
 674
 675         x -= 1;
 676         while (x > 0) {
 677                 c += 1;
 678                 x /= 10;
 679         }
 680
 681         return c;
 682 }
 683
 684
 685 static void
 686 MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars)
 687 {
 688         char *filename = malloc(PATH_MAX + 1);
 689         if (filename == NULL)
 690             error("Makefilename: malloc");
 691
 692         /* Process with strftime if Gflag is set. */
 693         if (Gflag != 0) {
 694           struct tm *local_tm;
 695
 696           /* Convert Gflag_time to a usable format */
 697           if ((local_tm = localtime(&Gflag_time)) == NULL) {
 698                   error("MakeTimedFilename: localtime");
 699           }
 700
 701           /* There's no good way to detect an error in strftime since a return
 702            * value of 0 isn't necessarily failure.
 703            */
 704           strftime(filename, PATH_MAX, orig_name, local_tm);
 705         } else {
 706           strncpy(filename, orig_name, PATH_MAX);
 707         }
 708
 709         if (cnt == 0 && max_chars == 0)
 710                 strncpy(buffer, filename, PATH_MAX + 1);
 711         else
 712                 if (snprintf(buffer, PATH_MAX + 1, "%s%0*d", filename, max_chars, cnt) > PATH_MAX)
 713                   /* Report an error if the filename is too large */
 714                   error("too many output files or filename is too long (> %d)", PATH_MAX);
 715         free(filename);
 716 }
 717
 718 static char *
 719 get_next_file(FILE *VFile, char *ptr)
 720 {
 721         char *ret;
 722
 723         ret = fgets(ptr, PATH_MAX, VFile);
 724         if (!ret)
 725                 return NULL;
 726
 727         if (ptr[strlen(ptr) - 1] == '\n')
 728                 ptr[strlen(ptr) - 1] = '\0';
 729
 730         return ret;
 731 }
 732
 733 #ifdef HAVE_CASPER
 734 static cap_channel_t *
 735 capdns_setup(void)
 736 {
 737         cap_channel_t *capcas, *capdnsloc;
 738         const char *types[1];
 739         int families[2];
 740
 741         capcas = cap_init();
 742         if (capcas == NULL)
 743                 error("unable to create casper process");
 744         capdnsloc = cap_service_open(capcas, "system.dns");
 745         /* Casper capability no longer needed. */
 746         cap_close(capcas);
 747         if (capdnsloc == NULL)
 748                 error("unable to open system.dns service");
 749         /* Limit system.dns to reverse DNS lookups. */
 750         types[0] = "ADDR";
 751         if (cap_dns_type_limit(capdnsloc, types, 1) < 0)
 752                 error("unable to limit access to system.dns service");
 753         families[0] = AF_INET;
 754         families[1] = AF_INET6;
 755         if (cap_dns_family_limit(capdnsloc, families, 2) < 0)
 756                 error("unable to limit access to system.dns service");
 757
 758         return (capdnsloc);
 759 }
 760 #endif  /* HAVE_CASPER */
 761
 762 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
 763 static int
 764 tstamp_precision_from_string(const char *precision)
 765 {
 766         if (strncmp(precision, "nano", strlen("nano")) == 0)
 767                 return PCAP_TSTAMP_PRECISION_NANO;
 768
 769         if (strncmp(precision, "micro", strlen("micro")) == 0)
 770                 return PCAP_TSTAMP_PRECISION_MICRO;
 771
 772         return -EINVAL;
 773 }
 774
 775 static const char *
 776 tstamp_precision_to_string(int precision)
 777 {
 778         switch (precision) {
 779
 780         case PCAP_TSTAMP_PRECISION_MICRO:
 781                 return "micro";
 782
 783         case PCAP_TSTAMP_PRECISION_NANO:
 784                 return "nano";
 785
 786         default:
 787                 return "unknown";
 788         }
 789 }
 790 #endif
 791
 792 #ifdef HAVE_CAPSICUM
 793 /*
 794  * Ensure that, on a dump file's descriptor, we have all the rights
 795  * necessary to make the standard I/O library work with an fdopen()ed
 796  * FILE * from that descriptor.
 797  *
 798  * A long time ago, in a galaxy far far away, AT&T decided that, instead
 799  * of providing separate APIs for getting and setting the FD_ flags on a
 800  * descriptor, getting and setting the O_ flags on a descriptor, and
 801  * locking files, they'd throw them all into a kitchen-sink fcntl() call
 802  * along the lines of ioctl(), the fact that ioctl() operations are
 803  * largely specific to particular character devices but fcntl() operations
 804  * are either generic to all descriptors or generic to all descriptors for
 805  * regular files nonwithstanding.
 806  *
 807  * The Capsicum people decided that fine-grained control of descriptor
 808  * operations was required, so that you need to grant permission for
 809  * reading, writing, seeking, and fcntl-ing.  The latter, courtesy of
 810  * AT&T's decision, means that "fcntl-ing" isn't a thing, but a motley
 811  * collection of things, so there are *individual* fcntls for which
 812  * permission needs to be granted.
 813  *
 814  * The FreeBSD standard I/O people implemented some optimizations that
 815  * requires that the standard I/O routines be able to determine whether
 816  * the descriptor for the FILE * is open append-only or not; as that
 817  * descriptor could have come from an open() rather than an fopen(),
 818  * that requires that it be able to do an F_GETFL fcntl() to read
 819  * the O_ flags.
 820  *
 821  * Tcpdump uses ftell() to determine how much data has been written
 822  * to a file in order to, when used with -C, determine when it's time
 823  * to rotate capture files.  ftell() therefore needs to do an lseek()
 824  * to find out the file offset and must, thanks to the aforementioned
 825  * optimization, also know whether the descriptor is open append-only
 826  * or not.
 827  *
 828  * The net result of all the above is that we need to grant CAP_SEEK,
 829  * CAP_WRITE, and CAP_FCNTL with the CAP_FCNTL_GETFL subcapability.
 830  *
 831  * Perhaps this is the universe's way of saying that either
 832  *
 833  *      1) there needs to be an fopenat() call and a pcap_dump_openat() call
 834  *         using it, so that Capsicum-capable tcpdump wouldn't need to do
 835  *         an fdopen()
 836  *
 837  * or
 838  *
 839  *      2) there needs to be a cap_fdopen() call in the FreeBSD standard
 840  *         I/O library that knows what rights are needed by the standard
 841  *         I/O library, based on the open mode, and assigns them, perhaps
 842  *         with an additional argument indicating, for example, whether
 843  *         seeking should be allowed, so that tcpdump doesn't need to know
 844  *         what the standard I/O library happens to require this week.
 845  */
 846 static void
 847 set_dumper_capsicum_rights(pcap_dumper_t *p)
 848 {
 849         int fd = fileno(pcap_dump_file(p));
 850         cap_rights_t rights;
 851
 852         cap_rights_init(&rights, CAP_SEEK, CAP_WRITE, CAP_FCNTL);
 853         if (cap_rights_limit(fd, &rights) < 0 && errno != ENOSYS) {
 854                 error("unable to limit dump descriptor");
 855         }
 856         if (cap_fcntls_limit(fd, CAP_FCNTL_GETFL) < 0 && errno != ENOSYS) {
 857                 error("unable to limit dump descriptor fcntls");
 858         }
 859 }
 860 #endif
 861
 862 /*
 863  * Copy arg vector into a new buffer, concatenating arguments with spaces.
 864  */
 865 static char *
 866 copy_argv(register char **argv)
 867 {
 868         register char **p;
 869         register u_int len = 0;
 870         char *buf;
 871         char *src, *dst;
 872
 873         p = argv;
 874         if (*p == NULL)
 875                 return 0;
 876
 877         while (*p)
 878                 len += strlen(*p++) + 1;
 879
 880         buf = (char *)malloc(len);
 881         if (buf == NULL)
 882                 error("copy_argv: malloc");
 883
 884         p = argv;
 885         dst = buf;
 886         while ((src = *p++) != NULL) {
 887                 while ((*dst++ = *src++) != '\0')
 888                         ;
 889                 dst[-1] = ' ';
 890         }
 891         dst[-1] = '\0';
 892
 893         return buf;
 894 }
 895
 896 /*
 897  * On Windows, we need to open the file in binary mode, so that
 898  * we get all the bytes specified by the size we get from "fstat()".
 899  * On UNIX, that's not necessary.  O_BINARY is defined on Windows;
 900  * we define it as 0 if it's not defined, so it does nothing.
 901  */
 902 #ifndef O_BINARY
 903 #define O_BINARY        0
 904 #endif
 905
 906 static char *
 907 read_infile(char *fname)
 908 {
 909         register int i, fd, cc;
 910         register char *cp;
 911         struct stat buf;
 912
 913         fd = open(fname, O_RDONLY|O_BINARY);
 914         if (fd < 0)
 915                 error("can't open %s: %s", fname, pcap_strerror(errno));
 916
 917         if (fstat(fd, &buf) < 0)
 918                 error("can't stat %s: %s", fname, pcap_strerror(errno));
 919
 920         cp = malloc((u_int)buf.st_size + 1);
 921         if (cp == NULL)
 922                 error("malloc(%d) for %s: %s", (u_int)buf.st_size + 1,
 923                         fname, pcap_strerror(errno));
 924         cc = read(fd, cp, (u_int)buf.st_size);
 925         if (cc < 0)
 926                 error("read %s: %s", fname, pcap_strerror(errno));
 927         if (cc != buf.st_size)
 928                 error("short read %s (%d != %d)", fname, cc, (int)buf.st_size);
 929
 930         close(fd);
 931         /* replace "# comment" with spaces */
 932         for (i = 0; i < cc; i++) {
 933                 if (cp[i] == '#')
 934                         while (i < cc && cp[i] != '\n')
 935                                 cp[i++] = ' ';
 936         }
 937         cp[cc] = '\0';
 938         return (cp);
 939 }
 940
 941 #ifdef HAVE_PCAP_FINDALLDEVS
 942 static long
 943 parse_interface_number(const char *device)
 944 {
 945         long devnum;
 946         char *end;
 947
 948         devnum = strtol(device, &end, 10);
 949         if (device != end && *end == '\0') {
 950                 /*
 951                  * It's all-numeric, but is it a valid number?
 952                  */
 953                 if (devnum <= 0) {
 954                         /*
 955                          * No, it's not an ordinal.
 956                          */
 957                         error("Invalid adapter index");
 958                 }
 959                 return (devnum);
 960         } else {
 961                 /*
 962                  * It's not all-numeric; return -1, so our caller
 963                  * knows that.
 964                  */
 965                 return (-1);
 966         }
 967 }
 968
 969 static char *
 970 find_interface_by_number(long devnum)
 971 {
 972         pcap_if_t *dev, *devlist;
 973         long i;
 974         char ebuf[PCAP_ERRBUF_SIZE];
 975         char *device;
 976
 977         if (pcap_findalldevs(&devlist, ebuf) < 0)
 978                 error("%s", ebuf);
 979         /*
 980          * Look for the devnum-th entry in the list of devices (1-based).
 981          */
 982         for (i = 0, dev = devlist; i < devnum-1 && dev != NULL;
 983             i++, dev = dev->next)
 984                 ;
 985         if (dev == NULL)
 986                 error("Invalid adapter index");
 987         device = strdup(dev->name);
 988         pcap_freealldevs(devlist);
 989         return (device);
 990 }
 991 #endif
 992
 993 static pcap_t *
 994 open_interface(const char *device, netdissect_options *ndo, char *ebuf)
 995 {
 996         pcap_t *pc;
 997 #ifdef HAVE_PCAP_CREATE
 998         int status;
 999         char *cp;
1000 #endif
1001
1002 #ifdef HAVE_PCAP_CREATE
1003         pc = pcap_create(device, ebuf);
1004         if (pc == NULL) {
1005                 /*
1006                  * If this failed with "No such device", that means
1007                  * the interface doesn't exist; return NULL, so that
1008                  * the caller can see whether the device name is
1009                  * actually an interface index.
1010                  */
1011                 if (strstr(ebuf, "No such device") != NULL)
1012                         return (NULL);
1013                 error("%s", ebuf);
1014         }
1015 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
1016         if (Jflag)
1017                 show_tstamp_types_and_exit(pc, device);
1018 #endif
1019 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
1020         status = pcap_set_tstamp_precision(pc, ndo->ndo_tstamp_precision);
1021         if (status != 0)
1022                 error("%s: Can't set %ssecond time stamp precision: %s",
1023                         device,
1024                         tstamp_precision_to_string(ndo->ndo_tstamp_precision),
1025                         pcap_statustostr(status));
1026 #endif
1027
1028 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
1029         if (immediate_mode) {
1030                 status = pcap_set_immediate_mode(pc, 1);
1031                 if (status != 0)
1032                         error("%s: Can't set immediate mode: %s",
1033                         device,
1034                         pcap_statustostr(status));
1035         }
1036 #endif
1037         /*
1038          * Is this an interface that supports monitor mode?
1039          */
1040         if (pcap_can_set_rfmon(pc) == 1)
1041                 supports_monitor_mode = 1;
1042         else
1043                 supports_monitor_mode = 0;
1044         status = pcap_set_snaplen(pc, ndo->ndo_snaplen);
1045         if (status != 0)
1046                 error("%s: Can't set snapshot length: %s",
1047                     device, pcap_statustostr(status));
1048         status = pcap_set_promisc(pc, !pflag);
1049         if (status != 0)
1050                 error("%s: Can't set promiscuous mode: %s",
1051                     device, pcap_statustostr(status));
1052         if (Iflag) {
1053                 status = pcap_set_rfmon(pc, 1);
1054                 if (status != 0)
1055                         error("%s: Can't set monitor mode: %s",
1056                             device, pcap_statustostr(status));
1057         }
1058         status = pcap_set_timeout(pc, 1000);
1059         if (status != 0)
1060                 error("%s: pcap_set_timeout failed: %s",
1061                     device, pcap_statustostr(status));
1062         if (Bflag != 0) {
1063                 status = pcap_set_buffer_size(pc, Bflag);
1064                 if (status != 0)
1065                         error("%s: Can't set buffer size: %s",
1066                             device, pcap_statustostr(status));
1067         }
1068 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
1069         if (jflag != -1) {
1070                 status = pcap_set_tstamp_type(pc, jflag);
1071                 if (status < 0)
1072                         error("%s: Can't set time stamp type: %s",
1073                               device, pcap_statustostr(status));
1074         }
1075 #endif
1076         status = pcap_activate(pc);
1077         if (status < 0) {
1078                 /*
1079                  * pcap_activate() failed.
1080                  */
1081                 cp = pcap_geterr(pc);
1082                 if (status == PCAP_ERROR)
1083                         error("%s", cp);
1084                 else if (status == PCAP_ERROR_NO_SUCH_DEVICE) {
1085                         /*
1086                          * Return an error for our caller to handle.
1087                          */
1088                         snprintf(ebuf, PCAP_ERRBUF_SIZE, "%s: %s\n(%s)",
1089                             device, pcap_statustostr(status), cp);
1090                         pcap_close(pc);
1091                         return (NULL);
1092                 } else if (status == PCAP_ERROR_PERM_DENIED && *cp != '\0')
1093                         error("%s: %s\n(%s)", device,
1094                             pcap_statustostr(status), cp);
1095 #ifdef __FreeBSD__
1096                 else if (status == PCAP_ERROR_RFMON_NOTSUP &&
1097                     strncmp(device, "wlan", 4) == 0) {
1098                         char parent[8], newdev[8];
1099                         char sysctl[32];
1100                         size_t s = sizeof(parent);
1101
1102                         snprintf(sysctl, sizeof(sysctl),
1103                             "net.wlan.%d.%%parent", atoi(device + 4));
1104                         sysctlbyname(sysctl, parent, &s, NULL, 0);
1105                         strlcpy(newdev, device, sizeof(newdev));
1106                         /* Suggest a new wlan device. */
1107                         newdev[strlen(newdev)-1]++;
1108                         error("%s is not a monitor mode VAP\n"
1109                             "To create a new monitor mode VAP use:\n"
1110                             "  ifconfig %s create wlandev %s wlanmode monitor\n"
1111                             "and use %s as the tcpdump interface",
1112                             device, newdev, parent, newdev);
1113                 }
1114 #endif
1115                 else
1116                         error("%s: %s", device,
1117                             pcap_statustostr(status));
1118         } else if (status > 0) {
1119                 /*
1120                  * pcap_activate() succeeded, but it's warning us
1121                  * of a problem it had.
1122                  */
1123                 cp = pcap_geterr(pc);
1124                 if (status == PCAP_WARNING)
1125                         warning("%s", cp);
1126                 else if (status == PCAP_WARNING_PROMISC_NOTSUP &&
1127                          *cp != '\0')
1128                         warning("%s: %s\n(%s)", device,
1129                             pcap_statustostr(status), cp);
1130                 else
1131                         warning("%s: %s", device,
1132                             pcap_statustostr(status));
1133         }
1134 #ifdef HAVE_PCAP_SETDIRECTION
1135         if (Qflag != -1) {
1136                 status = pcap_setdirection(pc, Qflag);
1137                 if (status != 0)
1138                         error("%s: pcap_setdirection() failed: %s",
1139                               device,  pcap_geterr(pc));
1140                 }
1141 #endif /* HAVE_PCAP_SETDIRECTION */
1142 #else /* HAVE_PCAP_CREATE */
1143         *ebuf = '\0';
1144         pc = pcap_open_live(device, ndo->ndo_snaplen, !pflag, 1000, ebuf);
1145         if (pc == NULL) {
1146                 /*
1147                  * If this failed with "No such device", that means
1148                  * the interface doesn't exist; return NULL, so that
1149                  * the caller can see whether the device name is
1150                  * actually an interface index.
1151                  */
1152                 if (strstr(ebuf, "No such device") != NULL)
1153                         return (NULL);
1154                 error("%s", ebuf);
1155         }
1156         if (*ebuf)
1157                 warning("%s", ebuf);
1158 #endif /* HAVE_PCAP_CREATE */
1159
1160         return (pc);
1161 }
1162
1163 int
1164 main(int argc, char **argv)
1165 {
1166         register int cnt, op, i;
1167         bpf_u_int32 localnet =0 , netmask = 0;
1168         int timezone_offset = 0;
1169         register char *cp, *infile, *cmdbuf, *device, *RFileName, *VFileName, *WFileName;
1170         pcap_handler callback;
1171         int dlt;
1172         const char *dlt_name;
1173         struct bpf_program fcode;
1174 #ifndef _WIN32
1175         RETSIGTYPE (*oldhandler)(int);
1176 #endif
1177         struct dump_info dumpinfo;
1178         u_char *pcap_userdata;
1179         char ebuf[PCAP_ERRBUF_SIZE];
1180         char VFileLine[PATH_MAX + 1];
1181         char *username = NULL;
1182         char *chroot_dir = NULL;
1183         char *ret = NULL;
1184         char *end;
1185 #ifdef HAVE_PCAP_FINDALLDEVS
1186         pcap_if_t *devlist;
1187         long devnum;
1188 #endif
1189         int status;
1190         FILE *VFile;
1191 #ifdef HAVE_CAPSICUM
1192         cap_rights_t rights;
1193         int cansandbox;
1194 #endif  /* HAVE_CAPSICUM */
1195         int Oflag = 1;                  /* run filter code optimizer */
1196         int yflag_dlt = -1;
1197         const char *yflag_dlt_name = NULL;
1198
1199         netdissect_options Ndo;
1200         netdissect_options *ndo = &Ndo;
1201
1202         /*
1203          * Initialize the netdissect code.
1204          */
1205         if (nd_init(ebuf, sizeof ebuf) == -1)
1206                 error("%s", ebuf);
1207
1208         memset(ndo, 0, sizeof(*ndo));
1209         ndo_set_function_pointers(ndo);
1210         ndo->ndo_snaplen = DEFAULT_SNAPLEN;
1211
1212         cnt = -1;
1213         device = NULL;
1214         infile = NULL;
1215         RFileName = NULL;
1216         VFileName = NULL;
1217         VFile = NULL;
1218         WFileName = NULL;
1219         dlt = -1;
1220         if ((cp = strrchr(argv[0], '/')) != NULL)
1221                 ndo->program_name = program_name = cp + 1;
1222         else
1223                 ndo->program_name = program_name = argv[0];
1224
1225 #ifdef _WIN32
1226         if (pcap_wsockinit() != 0)
1227                 error("Attempting to initialize Winsock failed");
1228 #endif /* _WIN32 */
1229
1230         /*
1231          * On platforms where the CPU doesn't support unaligned loads,
1232          * force unaligned accesses to abort with SIGBUS, rather than
1233          * being fixed up (slowly) by the OS kernel; on those platforms,
1234          * misaligned accesses are bugs, and we want tcpdump to crash so
1235          * that the bugs are reported.
1236          */
1237         if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
1238                 error("%s", ebuf);
1239
1240         while (
1241             (op = getopt_long(argc, argv, SHORTOPTS, longopts, NULL)) != -1)
1242                 switch (op) {
1243
1244                 case 'a':
1245                         /* compatibility for old -a */
1246                         break;
1247
1248                 case 'A':
1249                         ++ndo->ndo_Aflag;
1250                         break;
1251
1252                 case 'b':
1253                         ++ndo->ndo_bflag;
1254                         break;
1255
1256 #if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
1257                 case 'B':
1258                         Bflag = atoi(optarg)*1024;
1259                         if (Bflag <= 0)
1260                                 error("invalid packet buffer size %s", optarg);
1261                         break;
1262 #endif /* defined(HAVE_PCAP_CREATE) || defined(_WIN32) */
1263
1264                 case 'c':
1265                         cnt = atoi(optarg);
1266                         if (cnt <= 0)
1267                                 error("invalid packet count %s", optarg);
1268                         break;
1269
1270                 case 'C':
1271                         Cflag = atoi(optarg) * 1000000;
1272                         if (Cflag <= 0)
1273                                 error("invalid file size %s", optarg);
1274                         break;
1275
1276                 case 'd':
1277                         ++dflag;
1278                         break;
1279
1280                 case 'D':
1281                         Dflag++;
1282                         break;
1283
1284                 case 'L':
1285                         Lflag++;
1286                         break;
1287
1288                 case 'e':
1289                         ++ndo->ndo_eflag;
1290                         break;
1291
1292                 case 'E':
1293 #ifndef HAVE_LIBCRYPTO
1294                         warning("crypto code not compiled in");
1295 #endif
1296                         ndo->ndo_espsecret = optarg;
1297                         break;
1298
1299                 case 'f':
1300                         ++ndo->ndo_fflag;
1301                         break;
1302
1303                 case 'F':
1304                         infile = optarg;
1305                         break;
1306
1307                 case 'G':
1308                         Gflag = atoi(optarg);
1309                         if (Gflag < 0)
1310                                 error("invalid number of seconds %s", optarg);
1311
1312                         /* We will create one file initially. */
1313                         Gflag_count = 0;
1314
1315                         /* Grab the current time for rotation use. */
1316                         if ((Gflag_time = time(NULL)) == (time_t)-1) {
1317                                 error("main: can't get current time: %s",
1318                                     pcap_strerror(errno));
1319                         }
1320                         break;
1321
1322                 case 'h':
1323                         print_usage();
1324                         exit_tcpdump(0);
1325                         break;
1326
1327                 case 'H':
1328                         ++ndo->ndo_Hflag;
1329                         break;
1330
1331                 case 'i':
1332                         device = optarg;
1333                         break;
1334
1335 #ifdef HAVE_PCAP_CREATE
1336                 case 'I':
1337                         ++Iflag;
1338                         break;
1339 #endif /* HAVE_PCAP_CREATE */
1340
1341 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
1342                 case 'j':
1343                         jflag = pcap_tstamp_type_name_to_val(optarg);
1344                         if (jflag < 0)
1345                                 error("invalid time stamp type %s", optarg);
1346                         break;
1347
1348                 case 'J':
1349                         Jflag++;
1350                         break;
1351 #endif
1352
1353                 case 'l':
1354 #ifdef _WIN32
1355                         /*
1356                          * _IOLBF is the same as _IOFBF in Microsoft's C
1357                          * libraries; the only alternative they offer
1358                          * is _IONBF.
1359                          *
1360                          * XXX - this should really be checking for MSVC++,
1361                          * not _WIN32, if, for example, MinGW has its own
1362                          * C library that is more UNIX-compatible.
1363                          */
1364                         setvbuf(stdout, NULL, _IONBF, 0);
1365 #else /* _WIN32 */
1366 #ifdef HAVE_SETLINEBUF
1367                         setlinebuf(stdout);
1368 #else
1369                         setvbuf(stdout, NULL, _IOLBF, 0);
1370 #endif
1371 #endif /* _WIN32 */
1372                         break;
1373
1374                 case 'K':
1375                         ++ndo->ndo_Kflag;
1376                         break;
1377
1378                 case 'm':
1379                         if (nd_have_smi_support()) {
1380                                 if (nd_load_smi_module(optarg, ebuf, sizeof ebuf) == -1)
1381                                         error("%s", ebuf);
1382                         } else {
1383                                 (void)fprintf(stderr, "%s: ignoring option `-m %s' ",
1384                                               program_name, optarg);
1385                                 (void)fprintf(stderr, "(no libsmi support)\n");
1386                         }
1387                         break;
1388
1389                 case 'M':
1390                         /* TCP-MD5 shared secret */
1391 #ifndef HAVE_LIBCRYPTO
1392                         warning("crypto code not compiled in");
1393 #endif
1394                         ndo->ndo_sigsecret = optarg;
1395                         break;
1396
1397                 case 'n':
1398                         ++ndo->ndo_nflag;
1399                         break;
1400
1401                 case 'N':
1402                         ++ndo->ndo_Nflag;
1403                         break;
1404
1405                 case 'O':
1406                         Oflag = 0;
1407                         break;
1408
1409                 case 'p':
1410                         ++pflag;
1411                         break;
1412
1413                 case 'q':
1414                         ++ndo->ndo_qflag;
1415                         ++ndo->ndo_suppress_default_print;
1416                         break;
1417
1418 #ifdef HAVE_PCAP_SETDIRECTION
1419                 case 'Q':
1420                         if (ascii_strcasecmp(optarg, "in") == 0)
1421                                 Qflag = PCAP_D_IN;
1422                         else if (ascii_strcasecmp(optarg, "out") == 0)
1423                                 Qflag = PCAP_D_OUT;
1424                         else if (ascii_strcasecmp(optarg, "inout") == 0)
1425                                 Qflag = PCAP_D_INOUT;
1426                         else
1427                                 error("unknown capture direction `%s'", optarg);
1428                         break;
1429 #endif /* HAVE_PCAP_SETDIRECTION */
1430
1431                 case 'r':
1432                         RFileName = optarg;
1433                         break;
1434
1435                 case 's':
1436                         ndo->ndo_snaplen = strtol(optarg, &end, 0);
1437                         if (optarg == end || *end != '\0'
1438                             || ndo->ndo_snaplen < 0 || ndo->ndo_snaplen > MAXIMUM_SNAPLEN)
1439                                 error("invalid snaplen %s", optarg);
1440                         else if (ndo->ndo_snaplen == 0)
1441                                 ndo->ndo_snaplen = MAXIMUM_SNAPLEN;
1442                         break;
1443
1444                 case 'S':
1445                         ++ndo->ndo_Sflag;
1446                         break;
1447
1448                 case 't':
1449                         ++ndo->ndo_tflag;
1450                         break;
1451
1452                 case 'T':
1453                         if (ascii_strcasecmp(optarg, "vat") == 0)
1454                                 ndo->ndo_packettype = PT_VAT;
1455                         else if (ascii_strcasecmp(optarg, "wb") == 0)
1456                                 ndo->ndo_packettype = PT_WB;
1457                         else if (ascii_strcasecmp(optarg, "rpc") == 0)
1458                                 ndo->ndo_packettype = PT_RPC;
1459                         else if (ascii_strcasecmp(optarg, "rtp") == 0)
1460                                 ndo->ndo_packettype = PT_RTP;
1461                         else if (ascii_strcasecmp(optarg, "rtcp") == 0)
1462                                 ndo->ndo_packettype = PT_RTCP;
1463                         else if (ascii_strcasecmp(optarg, "snmp") == 0)
1464                                 ndo->ndo_packettype = PT_SNMP;
1465                         else if (ascii_strcasecmp(optarg, "cnfp") == 0)
1466                                 ndo->ndo_packettype = PT_CNFP;
1467                         else if (ascii_strcasecmp(optarg, "tftp") == 0)
1468                                 ndo->ndo_packettype = PT_TFTP;
1469                         else if (ascii_strcasecmp(optarg, "aodv") == 0)
1470                                 ndo->ndo_packettype = PT_AODV;
1471                         else if (ascii_strcasecmp(optarg, "carp") == 0)
1472                                 ndo->ndo_packettype = PT_CARP;
1473                         else if (ascii_strcasecmp(optarg, "radius") == 0)
1474                                 ndo->ndo_packettype = PT_RADIUS;
1475                         else if (ascii_strcasecmp(optarg, "zmtp1") == 0)
1476                                 ndo->ndo_packettype = PT_ZMTP1;
1477                         else if (ascii_strcasecmp(optarg, "vxlan") == 0)
1478                                 ndo->ndo_packettype = PT_VXLAN;
1479                         else if (ascii_strcasecmp(optarg, "pgm") == 0)
1480                                 ndo->ndo_packettype = PT_PGM;
1481                         else if (ascii_strcasecmp(optarg, "pgm_zmtp1") == 0)
1482                                 ndo->ndo_packettype = PT_PGM_ZMTP1;
1483                         else if (ascii_strcasecmp(optarg, "lmp") == 0)
1484                                 ndo->ndo_packettype = PT_LMP;
1485                         else if (ascii_strcasecmp(optarg, "resp") == 0)
1486                                 ndo->ndo_packettype = PT_RESP;
1487                         else
1488                                 error("unknown packet type `%s'", optarg);
1489                         break;
1490
1491                 case 'u':
1492                         ++ndo->ndo_uflag;
1493                         break;
1494
1495 #ifdef HAVE_PCAP_DUMP_FLUSH
1496                 case 'U':
1497                         ++Uflag;
1498                         break;
1499 #endif
1500
1501                 case 'v':
1502                         ++ndo->ndo_vflag;
1503                         break;
1504
1505                 case 'V':
1506                         VFileName = optarg;
1507                         break;
1508
1509                 case 'w':
1510                         WFileName = optarg;
1511                         break;
1512
1513                 case 'W':
1514                         Wflag = atoi(optarg);
1515                         if (Wflag <= 0)
1516                                 error("invalid number of output files %s", optarg);
1517                         WflagChars = getWflagChars(Wflag);
1518                         break;
1519
1520                 case 'x':
1521                         ++ndo->ndo_xflag;
1522                         ++ndo->ndo_suppress_default_print;
1523                         break;
1524
1525                 case 'X':
1526                         ++ndo->ndo_Xflag;
1527                         ++ndo->ndo_suppress_default_print;
1528                         break;
1529
1530                 case 'y':
1531                         yflag_dlt_name = optarg;
1532                         yflag_dlt =
1533                                 pcap_datalink_name_to_val(yflag_dlt_name);
1534                         if (yflag_dlt < 0)
1535                                 error("invalid data link type %s", yflag_dlt_name);
1536                         break;
1537
1538 #ifdef HAVE_PCAP_SET_PARSER_DEBUG
1539                 case 'Y':
1540                         {
1541                         /* Undocumented flag */
1542                         pcap_set_parser_debug(1);
1543                         }
1544                         break;
1545 #endif
1546                 case 'z':
1547                         zflag = optarg;
1548                         break;
1549
1550                 case 'Z':
1551                         username = optarg;
1552                         break;
1553
1554                 case '#':
1555                         ndo->ndo_packet_number = 1;
1556                         break;
1557
1558                 case OPTION_VERSION:
1559                         print_version();
1560                         exit_tcpdump(0);
1561                         break;
1562
1563 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
1564                 case OPTION_TSTAMP_PRECISION:
1565                         ndo->ndo_tstamp_precision = tstamp_precision_from_string(optarg);
1566                         if (ndo->ndo_tstamp_precision < 0)
1567                                 error("unsupported time stamp precision");
1568                         break;
1569 #endif
1570
1571 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
1572                 case OPTION_IMMEDIATE_MODE:
1573                         immediate_mode = 1;
1574                         break;
1575 #endif
1576
1577                 default:
1578                         print_usage();
1579                         exit_tcpdump(1);
1580                         /* NOTREACHED */
1581                 }
1582
1583 #ifdef HAVE_PCAP_FINDALLDEVS
1584         if (Dflag)
1585                 show_devices_and_exit();
1586 #endif
1587
1588         switch (ndo->ndo_tflag) {
1589
1590         case 0: /* Default */
1591         case 4: /* Default + Date*/
1592                 timezone_offset = gmt2local(0);
1593                 break;
1594
1595         case 1: /* No time stamp */
1596         case 2: /* Unix timeval style */
1597         case 3: /* Microseconds since previous packet */
1598         case 5: /* Microseconds since first packet */
1599                 break;
1600
1601         default: /* Not supported */
1602                 error("only -t, -tt, -ttt, -tttt and -ttttt are supported");
1603                 break;
1604         }
1605
1606         if (ndo->ndo_fflag != 0 && (VFileName != NULL || RFileName != NULL))
1607                 error("-f can not be used with -V or -r");
1608
1609         if (VFileName != NULL && RFileName != NULL)
1610                 error("-V and -r are mutually exclusive.");
1611
1612 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
1613         /*
1614          * If we're printing dissected packets to the standard output
1615          * rather than saving raw packets to a file, and the standard
1616          * output is a terminal, use immediate mode, as the user's
1617          * probably expecting to see packets pop up immediately.
1618          */
1619         if (WFileName == NULL && isatty(1))
1620                 immediate_mode = 1;
1621 #endif
1622
1623 #ifdef WITH_CHROOT
1624         /* if run as root, prepare for chrooting */
1625         if (getuid() == 0 || geteuid() == 0) {
1626                 /* future extensibility for cmd-line arguments */
1627                 if (!chroot_dir)
1628                         chroot_dir = WITH_CHROOT;
1629         }
1630 #endif
1631
1632 #ifdef WITH_USER
1633         /* if run as root, prepare for dropping root privileges */
1634         if (getuid() == 0 || geteuid() == 0) {
1635                 /* Run with '-Z root' to restore old behaviour */
1636                 if (!username)
1637                         username = WITH_USER;
1638         }
1639 #endif
1640
1641         if (RFileName != NULL || VFileName != NULL) {
1642                 /*
1643                  * If RFileName is non-null, it's the pathname of a
1644                  * savefile to read.  If VFileName is non-null, it's
1645                  * the pathname of a file containing a list of pathnames
1646                  * (one per line) of savefiles to read.
1647                  *
1648                  * In either case, we're reading a savefile, not doing
1649                  * a live capture.
1650                  */
1651 #ifndef _WIN32
1652                 /*
1653                  * We don't need network access, so relinquish any set-UID
1654                  * or set-GID privileges we have (if any).
1655                  *
1656                  * We do *not* want set-UID privileges when opening a
1657                  * trace file, as that might let the user read other
1658                  * people's trace files (especially if we're set-UID
1659                  * root).
1660                  */
1661                 if (setgid(getgid()) != 0 || setuid(getuid()) != 0 )
1662                         fprintf(stderr, "Warning: setgid/setuid failed !\n");
1663 #endif /* _WIN32 */
1664                 if (VFileName != NULL) {
1665                         if (VFileName[0] == '-' && VFileName[1] == '\0')
1666                                 VFile = stdin;
1667                         else
1668                                 VFile = fopen(VFileName, "r");
1669
1670                         if (VFile == NULL)
1671                                 error("Unable to open file: %s\n", pcap_strerror(errno));
1672
1673                         ret = get_next_file(VFile, VFileLine);
1674                         if (!ret)
1675                                 error("Nothing in %s\n", VFileName);
1676                         RFileName = VFileLine;
1677                 }
1678
1679 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
1680                 pd = pcap_open_offline_with_tstamp_precision(RFileName,
1681                     ndo->ndo_tstamp_precision, ebuf);
1682 #else
1683                 pd = pcap_open_offline(RFileName, ebuf);
1684 #endif
1685
1686                 if (pd == NULL)
1687                         error("%s", ebuf);
1688 #ifdef HAVE_CAPSICUM
1689                 cap_rights_init(&rights, CAP_READ);
1690                 if (cap_rights_limit(fileno(pcap_file(pd)), &rights) < 0 &&
1691                     errno != ENOSYS) {
1692                         error("unable to limit pcap descriptor");
1693                 }
1694 #endif
1695                 dlt = pcap_datalink(pd);
1696                 dlt_name = pcap_datalink_val_to_name(dlt);
1697                 if (dlt_name == NULL) {
1698                         fprintf(stderr, "reading from file %s, link-type %u\n",
1699                             RFileName, dlt);
1700                 } else {
1701                         fprintf(stderr,
1702                             "reading from file %s, link-type %s (%s)\n",
1703                             RFileName, dlt_name,
1704                             pcap_datalink_val_to_description(dlt));
1705                 }
1706         } else {
1707                 /*
1708                  * We're doing a live capture.
1709                  */
1710                 if (device == NULL) {
1711                         /*
1712                          * No interface was specified.  Pick one.
1713                          */
1714 #ifdef HAVE_PCAP_FINDALLDEVS
1715                         /*
1716                          * Find the list of interfaces, and pick
1717                          * the first interface.
1718                          */
1719                         if (pcap_findalldevs(&devlist, ebuf) >= 0 &&
1720                             devlist != NULL) {
1721                                 device = strdup(devlist->name);
1722                                 pcap_freealldevs(devlist);
1723                         }
1724 #else /* HAVE_PCAP_FINDALLDEVS */
1725                         /*
1726                          * Use whatever interface pcap_lookupdev()
1727                          * chooses.
1728                          */
1729                         device = pcap_lookupdev(ebuf);
1730 #endif
1731                         if (device == NULL)
1732                                 error("%s", ebuf);
1733                 }
1734
1735                 /*
1736                  * Try to open the interface with the specified name.
1737                  */
1738                 pd = open_interface(device, ndo, ebuf);
1739                 if (pd == NULL) {
1740                         /*
1741                          * That failed.  If we can get a list of
1742                          * interfaces, and the interface name
1743                          * is purely numeric, try to use it as
1744                          * a 1-based index in the list of
1745                          * interfaces.
1746                          */
1747 #ifdef HAVE_PCAP_FINDALLDEVS
1748                         devnum = parse_interface_number(device);
1749                         if (devnum == -1) {
1750                                 /*
1751                                  * It's not a number; just report
1752                                  * the open error and fail.
1753                                  */
1754                                 error("%s", ebuf);
1755                         }
1756
1757                         /*
1758                          * OK, it's a number; try to find the
1759                          * interface with that index, and try
1760                          * to open it.
1761                          *
1762                          * find_interface_by_number() exits if it
1763                          * couldn't be found.
1764                          */
1765                         device = find_interface_by_number(devnum);
1766                         pd = open_interface(device, ndo, ebuf);
1767                         if (pd == NULL)
1768                                 error("%s", ebuf);
1769 #else /* HAVE_PCAP_FINDALLDEVS */
1770                         /*
1771                          * We can't get a list of interfaces; just
1772                          * fail.
1773                          */
1774                         error("%s", ebuf);
1775 #endif /* HAVE_PCAP_FINDALLDEVS */
1776                 }
1777
1778                 /*
1779                  * Let user own process after socket has been opened.
1780                  */
1781 #ifndef _WIN32
1782                 if (setgid(getgid()) != 0 || setuid(getuid()) != 0)
1783                         fprintf(stderr, "Warning: setgid/setuid failed !\n");
1784 #endif /* _WIN32 */
1785 #if !defined(HAVE_PCAP_CREATE) && defined(_WIN32)
1786                 if(Bflag != 0)
1787                         if(pcap_setbuff(pd, Bflag)==-1){
1788                                 error("%s", pcap_geterr(pd));
1789                         }
1790 #endif /* !defined(HAVE_PCAP_CREATE) && defined(_WIN32) */
1791                 if (Lflag)
1792                         show_dlts_and_exit(pd, device);
1793                 if (yflag_dlt >= 0) {
1794 #ifdef HAVE_PCAP_SET_DATALINK
1795                         if (pcap_set_datalink(pd, yflag_dlt) < 0)
1796                                 error("%s", pcap_geterr(pd));
1797 #else
1798                         /*
1799                          * We don't actually support changing the
1800                          * data link type, so we only let them
1801                          * set it to what it already is.
1802                          */
1803                         if (yflag_dlt != pcap_datalink(pd)) {
1804                                 error("%s is not one of the DLTs supported by this device\n",
1805                                       yflag_dlt_name);
1806                         }
1807 #endif
1808                         (void)fprintf(stderr, "%s: data link type %s\n",
1809                                       program_name, yflag_dlt_name);
1810                         (void)fflush(stderr);
1811                 }
1812                 i = pcap_snapshot(pd);
1813                 if (ndo->ndo_snaplen < i) {
1814                         warning("snaplen raised from %d to %d", ndo->ndo_snaplen, i);
1815                         ndo->ndo_snaplen = i;
1816                 }
1817                 if(ndo->ndo_fflag != 0) {
1818                         if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
1819                                 warning("foreign (-f) flag used but: %s", ebuf);
1820                         }
1821                 }
1822
1823         }
1824         if (infile)
1825                 cmdbuf = read_infile(infile);
1826         else
1827                 cmdbuf = copy_argv(&argv[optind]);
1828
1829 #ifdef HAVE_PCAP_SET_OPTIMIZER_DEBUG
1830         pcap_set_optimizer_debug(dflag);
1831 #endif
1832         if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
1833                 error("%s", pcap_geterr(pd));
1834         if (dflag) {
1835                 bpf_dump(&fcode, dflag);
1836                 pcap_close(pd);
1837                 free(cmdbuf);
1838                 pcap_freecode(&fcode);
1839                 exit_tcpdump(0);
1840         }
1841
1842 #ifdef HAVE_CASPER
1843         if (!ndo->ndo_nflag)
1844                 capdns = capdns_setup();
1845 #endif  /* HAVE_CASPER */
1846
1847         init_print(ndo, localnet, netmask, timezone_offset);
1848
1849 #ifndef _WIN32
1850         (void)setsignal(SIGPIPE, cleanup);
1851         (void)setsignal(SIGTERM, cleanup);
1852         (void)setsignal(SIGINT, cleanup);
1853 #endif /* _WIN32 */
1854 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
1855         (void)setsignal(SIGCHLD, child_cleanup);
1856 #endif
1857         /* Cooperate with nohup(1) */
1858 #ifndef _WIN32
1859         if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL)
1860                 (void)setsignal(SIGHUP, oldhandler);
1861 #endif /* _WIN32 */
1862
1863 #ifndef _WIN32
1864         /*
1865          * If a user name was specified with "-Z", attempt to switch to
1866          * that user's UID.  This would probably be used with sudo,
1867          * to allow tcpdump to be run in a special restricted
1868          * account (if you just want to allow users to open capture
1869          * devices, and can't just give users that permission,
1870          * you'd make tcpdump set-UID or set-GID).
1871          *
1872          * Tcpdump doesn't necessarily write only to one savefile;
1873          * the general only way to allow a -Z instance to write to
1874          * savefiles as the user under whose UID it's run, rather
1875          * than as the user specified with -Z, would thus be to switch
1876          * to the original user ID before opening a capture file and
1877          * then switch back to the -Z user ID after opening the savefile.
1878          * Switching to the -Z user ID only after opening the first
1879          * savefile doesn't handle the general case.
1880          */
1881
1882         if (getuid() == 0 || geteuid() == 0) {
1883 #ifdef HAVE_LIBCAP_NG
1884                 /* Initialize capng */
1885                 capng_clear(CAPNG_SELECT_BOTH);
1886                 if (username) {
1887                         capng_updatev(
1888                                 CAPNG_ADD,
1889                                 CAPNG_PERMITTED | CAPNG_EFFECTIVE,
1890                                 CAP_SETUID,
1891                                 CAP_SETGID,
1892                                 -1);
1893                 }
1894                 if (chroot_dir) {
1895                         capng_update(
1896                                 CAPNG_ADD,
1897                                 CAPNG_PERMITTED | CAPNG_EFFECTIVE,
1898                                 CAP_SYS_CHROOT
1899                                 );
1900                 }
1901
1902                 if (WFileName) {
1903                         capng_update(
1904                                 CAPNG_ADD,
1905                                 CAPNG_PERMITTED | CAPNG_EFFECTIVE,
1906                                 CAP_DAC_OVERRIDE
1907                                 );
1908                 }
1909                 capng_apply(CAPNG_SELECT_BOTH);
1910 #endif /* HAVE_LIBCAP_NG */
1911                 if (username || chroot_dir)
1912                         droproot(username, chroot_dir);
1913
1914         }
1915 #endif /* _WIN32 */
1916
1917         if (pcap_setfilter(pd, &fcode) < 0)
1918                 error("%s", pcap_geterr(pd));
1919 #ifdef HAVE_CAPSICUM
1920         if (RFileName == NULL && VFileName == NULL) {
1921                 static const unsigned long cmds[] = { BIOCGSTATS, BIOCROTZBUF };
1922
1923                 /*
1924                  * The various libpcap devices use a combination of
1925                  * read (bpf), ioctl (bpf, netmap), poll (netmap).
1926                  * Grant the relevant access rights, sorted by name.
1927                  */
1928                 cap_rights_init(&rights, CAP_EVENT, CAP_IOCTL, CAP_READ);
1929                 if (cap_rights_limit(pcap_fileno(pd), &rights) < 0 &&
1930                     errno != ENOSYS) {
1931                         error("unable to limit pcap descriptor");
1932                 }
1933                 if (cap_ioctls_limit(pcap_fileno(pd), cmds,
1934                     sizeof(cmds) / sizeof(cmds[0])) < 0 && errno != ENOSYS) {
1935                         error("unable to limit ioctls on pcap descriptor");
1936                 }
1937         }
1938 #endif
1939         if (WFileName) {
1940                 pcap_dumper_t *p;
1941                 /* Do not exceed the default PATH_MAX for files. */
1942                 dumpinfo.CurrentFileName = (char *)malloc(PATH_MAX + 1);
1943
1944                 if (dumpinfo.CurrentFileName == NULL)
1945                         error("malloc of dumpinfo.CurrentFileName");
1946
1947                 /* We do not need numbering for dumpfiles if Cflag isn't set. */
1948                 if (Cflag != 0)
1949                   MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, WflagChars);
1950                 else
1951                   MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, 0);
1952
1953                 p = pcap_dump_open(pd, dumpinfo.CurrentFileName);
1954 #ifdef HAVE_LIBCAP_NG
1955                 /* Give up CAP_DAC_OVERRIDE capability.
1956                  * Only allow it to be restored if the -C or -G flag have been
1957                  * set since we may need to create more files later on.
1958                  */
1959                 capng_update(
1960                         CAPNG_DROP,
1961                         (Cflag || Gflag ? 0 : CAPNG_PERMITTED)
1962                                 | CAPNG_EFFECTIVE,
1963                         CAP_DAC_OVERRIDE
1964                         );
1965                 capng_apply(CAPNG_SELECT_BOTH);
1966 #endif /* HAVE_LIBCAP_NG */
1967                 if (p == NULL)
1968                         error("%s", pcap_geterr(pd));
1969 #ifdef HAVE_CAPSICUM
1970                 set_dumper_capsicum_rights(p);
1971 #endif
1972                 if (Cflag != 0 || Gflag != 0) {
1973 #ifdef HAVE_CAPSICUM
1974                         dumpinfo.WFileName = strdup(basename(WFileName));
1975                         if (dumpinfo.WFileName == NULL) {
1976                                 error("Unable to allocate memory for file %s",
1977                                     WFileName);
1978                         }
1979                         dumpinfo.dirfd = open(dirname(WFileName),
1980                             O_DIRECTORY | O_RDONLY);
1981                         if (dumpinfo.dirfd < 0) {
1982                                 error("unable to open directory %s",
1983                                     dirname(WFileName));
1984                         }
1985                         cap_rights_init(&rights, CAP_CREATE, CAP_FCNTL,
1986                             CAP_FTRUNCATE, CAP_LOOKUP, CAP_SEEK, CAP_WRITE);
1987                         if (cap_rights_limit(dumpinfo.dirfd, &rights) < 0 &&
1988                             errno != ENOSYS) {
1989                                 error("unable to limit directory rights");
1990                         }
1991                         if (cap_fcntls_limit(dumpinfo.dirfd, CAP_FCNTL_GETFL) < 0 &&
1992                             errno != ENOSYS) {
1993                                 error("unable to limit dump descriptor fcntls");
1994                         }
1995 #else   /* !HAVE_CAPSICUM */
1996                         dumpinfo.WFileName = WFileName;
1997 #endif
1998                         callback = dump_packet_and_trunc;
1999                         dumpinfo.pd = pd;
2000                         dumpinfo.p = p;
2001                         pcap_userdata = (u_char *)&dumpinfo;
2002                 } else {
2003                         callback = dump_packet;
2004                         pcap_userdata = (u_char *)p;
2005                 }
2006 #ifdef HAVE_PCAP_DUMP_FLUSH
2007                 if (Uflag)
2008                         pcap_dump_flush(p);
2009 #endif
2010         } else {
2011                 dlt = pcap_datalink(pd);
2012                 ndo->ndo_if_printer = get_if_printer(ndo, dlt);
2013                 callback = print_packet;
2014                 pcap_userdata = (u_char *)ndo;
2015         }
2016
2017 #ifdef SIGNAL_REQ_INFO
2018         /*
2019          * We can't get statistics when reading from a file rather
2020          * than capturing from a device.
2021          */
2022         if (RFileName == NULL)
2023                 (void)setsignal(SIGNAL_REQ_INFO, requestinfo);
2024 #endif
2025
2026         if (ndo->ndo_vflag > 0 && WFileName) {
2027                 /*
2028                  * When capturing to a file, "-v" means tcpdump should,
2029                  * every 10 seconds, "v"erbosely report the number of
2030                  * packets captured.
2031                  */
2032 #ifdef USE_WIN32_MM_TIMER
2033                 /* call verbose_stats_dump() each 1000 +/-100msec */
2034                 timer_id = timeSetEvent(1000, 100, verbose_stats_dump, 0, TIME_PERIODIC);
2035                 setvbuf(stderr, NULL, _IONBF, 0);
2036 #elif defined(HAVE_ALARM)
2037                 (void)setsignal(SIGALRM, verbose_stats_dump);
2038                 alarm(1);
2039 #endif
2040         }
2041
2042         if (RFileName == NULL) {
2043                 /*
2044                  * Live capture (if -V was specified, we set RFileName
2045                  * to a file from the -V file).  Print a message to
2046                  * the standard error on UN*X.
2047                  */
2048                 if (!ndo->ndo_vflag && !WFileName) {
2049                         (void)fprintf(stderr,
2050                             "%s: verbose output suppressed, use -v or -vv for full protocol decode\n",
2051                             program_name);
2052                 } else
2053                         (void)fprintf(stderr, "%s: ", program_name);
2054                 dlt = pcap_datalink(pd);
2055                 dlt_name = pcap_datalink_val_to_name(dlt);
2056                 if (dlt_name == NULL) {
2057                         (void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n",
2058                             device, dlt, ndo->ndo_snaplen);
2059                 } else {
2060                         (void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n",
2061                             device, dlt_name,
2062                             pcap_datalink_val_to_description(dlt), ndo->ndo_snaplen);
2063                 }
2064                 (void)fflush(stderr);
2065         }
2066
2067 #ifdef HAVE_CAPSICUM
2068         cansandbox = (VFileName == NULL && zflag == NULL);
2069 #ifdef HAVE_CASPER
2070         cansandbox = (cansandbox && (ndo->ndo_nflag || capdns != NULL));
2071 #else
2072         cansandbox = (cansandbox && ndo->ndo_nflag);
2073 #endif  /* HAVE_CASPER */
2074         if (cansandbox && cap_enter() < 0 && errno != ENOSYS)
2075                 error("unable to enter the capability mode");
2076 #endif  /* HAVE_CAPSICUM */
2077
2078         do {
2079                 status = pcap_loop(pd, cnt, callback, pcap_userdata);
2080                 if (WFileName == NULL) {
2081                         /*
2082                          * We're printing packets.  Flush the printed output,
2083                          * so it doesn't get intermingled with error output.
2084                          */
2085                         if (status == -2) {
2086                                 /*
2087                                  * We got interrupted, so perhaps we didn't
2088                                  * manage to finish a line we were printing.
2089                                  * Print an extra newline, just in case.
2090                                  */
2091                                 putchar('\n');
2092                         }
2093                         (void)fflush(stdout);
2094                 }
2095                 if (status == -2) {
2096                         /*
2097                          * We got interrupted. If we are reading multiple
2098                          * files (via -V) set these so that we stop.
2099                          */
2100                         VFileName = NULL;
2101                         ret = NULL;
2102                 }
2103                 if (status == -1) {
2104                         /*
2105                          * Error.  Report it.
2106                          */
2107                         (void)fprintf(stderr, "%s: pcap_loop: %s\n",
2108                             program_name, pcap_geterr(pd));
2109                 }
2110                 if (RFileName == NULL) {
2111                         /*
2112                          * We're doing a live capture.  Report the capture
2113                          * statistics.
2114                          */
2115                         info(1);
2116                 }
2117                 pcap_close(pd);
2118                 if (VFileName != NULL) {
2119                         ret = get_next_file(VFile, VFileLine);
2120                         if (ret) {
2121                                 int new_dlt;
2122
2123                                 RFileName = VFileLine;
2124                                 pd = pcap_open_offline(RFileName, ebuf);
2125                                 if (pd == NULL)
2126                                         error("%s", ebuf);
2127 #ifdef HAVE_CAPSICUM
2128                                 cap_rights_init(&rights, CAP_READ);
2129                                 if (cap_rights_limit(fileno(pcap_file(pd)),
2130                                     &rights) < 0 && errno != ENOSYS) {
2131                                         error("unable to limit pcap descriptor");
2132                                 }
2133 #endif
2134                                 new_dlt = pcap_datalink(pd);
2135                                 if (new_dlt != dlt) {
2136                                         /*
2137                                          * The new file has a different
2138                                          * link-layer header type from the
2139                                          * previous one.
2140                                          */
2141                                         if (WFileName != NULL) {
2142                                                 /*
2143                                                  * We're writing raw packets
2144                                                  * that match the filter to
2145                                                  * a pcap file.  pcap files
2146                                                  * don't support multiple
2147                                                  * different link-layer
2148                                                  * header types, so we fail
2149                                                  * here.
2150                                                  */
2151                                                 error("%s: new dlt does not match original", RFileName);
2152                                         }
2153
2154                                         /*
2155                                          * We're printing the decoded packets;
2156                                          * switch to the new DLT.
2157                                          *
2158                                          * To do that, we need to change
2159                                          * the printer, change the DLT name,
2160                                          * and recompile the filter with
2161                                          * the new DLT.
2162                                          */
2163                                         dlt = new_dlt;
2164                                         ndo->ndo_if_printer = get_if_printer(ndo, dlt);
2165                                         if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
2166                                                 error("%s", pcap_geterr(pd));
2167                                 }
2168
2169                                 /*
2170                                  * Set the filter on the new file.
2171                                  */
2172                                 if (pcap_setfilter(pd, &fcode) < 0)
2173                                         error("%s", pcap_geterr(pd));
2174
2175                                 /*
2176                                  * Report the new file.
2177                                  */
2178                                 dlt_name = pcap_datalink_val_to_name(dlt);
2179                                 if (dlt_name == NULL) {
2180                                         fprintf(stderr, "reading from file %s, link-type %u\n",
2181                                             RFileName, dlt);
2182                                 } else {
2183                                         fprintf(stderr,
2184                                         "reading from file %s, link-type %s (%s)\n",
2185                                             RFileName, dlt_name,
2186                                             pcap_datalink_val_to_description(dlt));
2187                                 }
2188                         }
2189                 }
2190         }
2191         while (ret != NULL);
2192
2193         free(cmdbuf);
2194         pcap_freecode(&fcode);
2195         exit_tcpdump(status == -1 ? 1 : 0);
2196 }
2197
2198 /* make a clean exit on interrupts */
2199 static RETSIGTYPE
2200 cleanup(int signo _U_)
2201 {
2202 #ifdef USE_WIN32_MM_TIMER
2203         if (timer_id)
2204                 timeKillEvent(timer_id);
2205         timer_id = 0;
2206 #elif defined(HAVE_ALARM)
2207         alarm(0);
2208 #endif
2209
2210 #ifdef HAVE_PCAP_BREAKLOOP
2211         /*
2212          * We have "pcap_breakloop()"; use it, so that we do as little
2213          * as possible in the signal handler (it's probably not safe
2214          * to do anything with standard I/O streams in a signal handler -
2215          * the ANSI C standard doesn't say it is).
2216          */
2217         pcap_breakloop(pd);
2218 #else
2219         /*
2220          * We don't have "pcap_breakloop()"; this isn't safe, but
2221          * it's the best we can do.  Print the summary if we're
2222          * not reading from a savefile - i.e., if we're doing a
2223          * live capture - and exit.
2224          */
2225         if (pd != NULL && pcap_file(pd) == NULL) {
2226                 /*
2227                  * We got interrupted, so perhaps we didn't
2228                  * manage to finish a line we were printing.
2229                  * Print an extra newline, just in case.
2230                  */
2231                 putchar('\n');
2232                 (void)fflush(stdout);
2233                 info(1);
2234         }
2235         exit_tcpdump(0);
2236 #endif
2237 }
2238
2239 /*
2240   On windows, we do not use a fork, so we do not care less about
2241   waiting a child processes to die
2242  */
2243 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
2244 static RETSIGTYPE
2245 child_cleanup(int signo _U_)
2246 {
2247   wait(NULL);
2248 }
2249 #endif /* HAVE_FORK && HAVE_VFORK */
2250
2251 static void
2252 info(register int verbose)
2253 {
2254         struct pcap_stat stats;
2255
2256         /*
2257          * Older versions of libpcap didn't set ps_ifdrop on some
2258          * platforms; initialize it to 0 to handle that.
2259          */
2260         stats.ps_ifdrop = 0;
2261         if (pcap_stats(pd, &stats) < 0) {
2262                 (void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd));
2263                 infoprint = 0;
2264                 return;
2265         }
2266
2267         if (!verbose)
2268                 fprintf(stderr, "%s: ", program_name);
2269
2270         (void)fprintf(stderr, "%u packet%s captured", packets_captured,
2271             PLURAL_SUFFIX(packets_captured));
2272         if (!verbose)
2273                 fputs(", ", stderr);
2274         else
2275                 putc('\n', stderr);
2276         (void)fprintf(stderr, "%u packet%s received by filter", stats.ps_recv,
2277             PLURAL_SUFFIX(stats.ps_recv));
2278         if (!verbose)
2279                 fputs(", ", stderr);
2280         else
2281                 putc('\n', stderr);
2282         (void)fprintf(stderr, "%u packet%s dropped by kernel", stats.ps_drop,
2283             PLURAL_SUFFIX(stats.ps_drop));
2284         if (stats.ps_ifdrop != 0) {
2285                 if (!verbose)
2286                         fputs(", ", stderr);
2287                 else
2288                         putc('\n', stderr);
2289                 (void)fprintf(stderr, "%u packet%s dropped by interface\n",
2290                     stats.ps_ifdrop, PLURAL_SUFFIX(stats.ps_ifdrop));
2291         } else
2292                 putc('\n', stderr);
2293         infoprint = 0;
2294 }
2295
2296 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
2297 #ifdef HAVE_FORK
2298 #define fork_subprocess() fork()
2299 #else
2300 #define fork_subprocess() vfork()
2301 #endif
2302 static void
2303 compress_savefile(const char *filename)
2304 {
2305         pid_t child;
2306
2307         child = fork_subprocess();
2308         if (child == -1) {
2309                 fprintf(stderr,
2310                         "compress_savefile: fork failed: %s\n",
2311                         pcap_strerror(errno));
2312                 return;
2313         }
2314         if (child != 0) {
2315                 /* Parent process. */
2316                 return;
2317         }
2318
2319         /*
2320          * Child process.
2321          * Set to lowest priority so that this doesn't disturb the capture.
2322          */
2323 #ifdef NZERO
2324         setpriority(PRIO_PROCESS, 0, NZERO - 1);
2325 #else
2326         setpriority(PRIO_PROCESS, 0, 19);
2327 #endif
2328         if (execlp(zflag, zflag, filename, (char *)NULL) == -1)
2329                 fprintf(stderr,
2330                         "compress_savefile: execlp(%s, %s) failed: %s\n",
2331                         zflag,
2332                         filename,
2333                         pcap_strerror(errno));
2334 #ifdef HAVE_FORK
2335         exit(1);
2336 #else
2337         _exit(1);
2338 #endif
2339 }
2340 #else  /* HAVE_FORK && HAVE_VFORK */
2341 static void
2342 compress_savefile(const char *filename)
2343 {
2344         fprintf(stderr,
2345                 "compress_savefile failed. Functionality not implemented under your system\n");
2346 }
2347 #endif /* HAVE_FORK && HAVE_VFORK */
2348
2349 static void
2350 dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
2351 {
2352         struct dump_info *dump_info;
2353
2354         ++packets_captured;
2355
2356         ++infodelay;
2357
2358         dump_info = (struct dump_info *)user;
2359
2360         /*
2361          * XXX - this won't force the file to rotate on the specified time
2362          * boundary, but it will rotate on the first packet received after the
2363          * specified Gflag number of seconds. Note: if a Gflag time boundary
2364          * and a Cflag size boundary coincide, the time rotation will occur
2365          * first thereby cancelling the Cflag boundary (since the file should
2366          * be 0).
2367          */
2368         if (Gflag != 0) {
2369                 /* Check if it is time to rotate */
2370                 time_t t;
2371
2372                 /* Get the current time */
2373                 if ((t = time(NULL)) == (time_t)-1) {
2374                         error("dump_and_trunc_packet: can't get current_time: %s",
2375                             pcap_strerror(errno));
2376                 }
2377
2378
2379                 /* If the time is greater than the specified window, rotate */
2380                 if (t - Gflag_time >= Gflag) {
2381 #ifdef HAVE_CAPSICUM
2382                         FILE *fp;
2383                         int fd;
2384 #endif
2385
2386                         /* Update the Gflag_time */
2387                         Gflag_time = t;
2388                         /* Update Gflag_count */
2389                         Gflag_count++;
2390                         /*
2391                          * Close the current file and open a new one.
2392                          */
2393                         pcap_dump_close(dump_info->p);
2394
2395                         /*
2396                          * Compress the file we just closed, if the user asked for it
2397                          */
2398                         if (zflag != NULL)
2399                                 compress_savefile(dump_info->CurrentFileName);
2400
2401                         /*
2402                          * Check to see if we've exceeded the Wflag (when
2403                          * not using Cflag).
2404                          */
2405                         if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) {
2406                                 (void)fprintf(stderr, "Maximum file limit reached: %d\n",
2407                                     Wflag);
2408                                 info(1);
2409                                 exit_tcpdump(0);
2410                                 /* NOTREACHED */
2411                         }
2412                         if (dump_info->CurrentFileName != NULL)
2413                                 free(dump_info->CurrentFileName);
2414                         /* Allocate space for max filename + \0. */
2415                         dump_info->CurrentFileName = (char *)malloc(PATH_MAX + 1);
2416                         if (dump_info->CurrentFileName == NULL)
2417                                 error("dump_packet_and_trunc: malloc");
2418                         /*
2419                          * Gflag was set otherwise we wouldn't be here. Reset the count
2420                          * so multiple files would end with 1,2,3 in the filename.
2421                          * The counting is handled with the -C flow after this.
2422                          */
2423                         Cflag_count = 0;
2424
2425                         /*
2426                          * This is always the first file in the Cflag
2427                          * rotation: e.g. 0
2428                          * We also don't need numbering if Cflag is not set.
2429                          */
2430                         if (Cflag != 0)
2431                                 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0,
2432                                     WflagChars);
2433                         else
2434                                 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0, 0);
2435
2436 #ifdef HAVE_LIBCAP_NG
2437                         capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
2438                         capng_apply(CAPNG_SELECT_BOTH);
2439 #endif /* HAVE_LIBCAP_NG */
2440 #ifdef HAVE_CAPSICUM
2441                         fd = openat(dump_info->dirfd,
2442                             dump_info->CurrentFileName,
2443                             O_CREAT | O_WRONLY | O_TRUNC, 0644);
2444                         if (fd < 0) {
2445                                 error("unable to open file %s",
2446                                     dump_info->CurrentFileName);
2447                         }
2448                         fp = fdopen(fd, "w");
2449                         if (fp == NULL) {
2450                                 error("unable to fdopen file %s",
2451                                     dump_info->CurrentFileName);
2452                         }
2453                         dump_info->p = pcap_dump_fopen(dump_info->pd, fp);
2454 #else   /* !HAVE_CAPSICUM */
2455                         dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
2456 #endif
2457 #ifdef HAVE_LIBCAP_NG
2458                         capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
2459                         capng_apply(CAPNG_SELECT_BOTH);
2460 #endif /* HAVE_LIBCAP_NG */
2461                         if (dump_info->p == NULL)
2462                                 error("%s", pcap_geterr(pd));
2463 #ifdef HAVE_CAPSICUM
2464                         set_dumper_capsicum_rights(dump_info->p);
2465 #endif
2466                 }
2467         }
2468
2469         /*
2470          * XXX - this won't prevent capture files from getting
2471          * larger than Cflag - the last packet written to the
2472          * file could put it over Cflag.
2473          */
2474         if (Cflag != 0) {
2475                 long size = pcap_dump_ftell(dump_info->p);
2476
2477                 if (size == -1)
2478                         error("ftell fails on output file");
2479                 if (size > Cflag) {
2480 #ifdef HAVE_CAPSICUM
2481                         FILE *fp;
2482                         int fd;
2483 #endif
2484
2485                         /*
2486                          * Close the current file and open a new one.
2487                          */
2488                         pcap_dump_close(dump_info->p);
2489
2490                         /*
2491                          * Compress the file we just closed, if the user
2492                          * asked for it.
2493                          */
2494                         if (zflag != NULL)
2495                                 compress_savefile(dump_info->CurrentFileName);
2496
2497                         Cflag_count++;
2498                         if (Wflag > 0) {
2499                                 if (Cflag_count >= Wflag)
2500                                         Cflag_count = 0;
2501                         }
2502                         if (dump_info->CurrentFileName != NULL)
2503                                 free(dump_info->CurrentFileName);
2504                         dump_info->CurrentFileName = (char *)malloc(PATH_MAX + 1);
2505                         if (dump_info->CurrentFileName == NULL)
2506                                 error("dump_packet_and_trunc: malloc");
2507                         MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, Cflag_count, WflagChars);
2508 #ifdef HAVE_LIBCAP_NG
2509                         capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
2510                         capng_apply(CAPNG_SELECT_BOTH);
2511 #endif /* HAVE_LIBCAP_NG */
2512 #ifdef HAVE_CAPSICUM
2513                         fd = openat(dump_info->dirfd, dump_info->CurrentFileName,
2514                             O_CREAT | O_WRONLY | O_TRUNC, 0644);
2515                         if (fd < 0) {
2516                                 error("unable to open file %s",
2517                                     dump_info->CurrentFileName);
2518                         }
2519                         fp = fdopen(fd, "w");
2520                         if (fp == NULL) {
2521                                 error("unable to fdopen file %s",
2522                                     dump_info->CurrentFileName);
2523                         }
2524                         dump_info->p = pcap_dump_fopen(dump_info->pd, fp);
2525 #else   /* !HAVE_CAPSICUM */
2526                         dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
2527 #endif
2528 #ifdef HAVE_LIBCAP_NG
2529                         capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
2530                         capng_apply(CAPNG_SELECT_BOTH);
2531 #endif /* HAVE_LIBCAP_NG */
2532                         if (dump_info->p == NULL)
2533                                 error("%s", pcap_geterr(pd));
2534 #ifdef HAVE_CAPSICUM
2535                         set_dumper_capsicum_rights(dump_info->p);
2536 #endif
2537                 }
2538         }
2539
2540         pcap_dump((u_char *)dump_info->p, h, sp);
2541 #ifdef HAVE_PCAP_DUMP_FLUSH
2542         if (Uflag)
2543                 pcap_dump_flush(dump_info->p);
2544 #endif
2545
2546         --infodelay;
2547         if (infoprint)
2548                 info(0);
2549 }
2550
2551 static void
2552 dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
2553 {
2554         ++packets_captured;
2555
2556         ++infodelay;
2557
2558         pcap_dump(user, h, sp);
2559 #ifdef HAVE_PCAP_DUMP_FLUSH
2560         if (Uflag)
2561                 pcap_dump_flush((pcap_dumper_t *)user);
2562 #endif
2563
2564         --infodelay;
2565         if (infoprint)
2566                 info(0);
2567 }
2568
2569 static void
2570 print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
2571 {
2572         ++packets_captured;
2573
2574         ++infodelay;
2575
2576         pretty_print_packet((netdissect_options *)user, h, sp, packets_captured);
2577
2578         --infodelay;
2579         if (infoprint)
2580                 info(0);
2581 }
2582
2583 #ifdef _WIN32
2584         /*
2585          * XXX - there should really be libpcap calls to get the version
2586          * number as a string (the string would be generated from #defines
2587          * at run time, so that it's not generated from string constants
2588          * in the library, as, on many UNIX systems, those constants would
2589          * be statically linked into the application executable image, and
2590          * would thus reflect the version of libpcap on the system on
2591          * which the application was *linked*, not the system on which it's
2592          * *running*.
2593          *
2594          * That routine should be documented, unlike the "version[]"
2595          * string, so that UNIX vendors providing their own libpcaps
2596          * don't omit it (as a couple of vendors have...).
2597          *
2598          * Packet.dll should perhaps also export a routine to return the
2599          * version number of the Packet.dll code, to supply the
2600          * "Wpcap_version" information on Windows.
2601          */
2602         char WDversion[]="current-git.tcpdump.org";
2603 #if !defined(HAVE_GENERATED_VERSION)
2604         char version[]="current-git.tcpdump.org";
2605 #endif
2606         char pcap_version[]="current-git.tcpdump.org";
2607         char Wpcap_version[]="3.1";
2608 #endif
2609
2610 #ifdef SIGNAL_REQ_INFO
2611 RETSIGTYPE requestinfo(int signo _U_)
2612 {
2613         if (infodelay)
2614                 ++infoprint;
2615         else
2616                 info(0);
2617 }
2618 #endif
2619
2620 /*
2621  * Called once each second in verbose mode while dumping to file
2622  */
2623 #ifdef USE_WIN32_MM_TIMER
2624 void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_,
2625                                   DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_)
2626 {
2627         if (infodelay == 0)
2628                 fprintf(stderr, "Got %u\r", packets_captured);
2629 }
2630 #elif defined(HAVE_ALARM)
2631 static void verbose_stats_dump(int sig _U_)
2632 {
2633         if (infodelay == 0)
2634                 fprintf(stderr, "Got %u\r", packets_captured);
2635         alarm(1);
2636 }
2637 #endif
2638
2639 USES_APPLE_DEPRECATED_API
2640 static void
2641 print_version(void)
2642 {
2643         extern char version[];
2644 #ifndef HAVE_PCAP_LIB_VERSION
2645 #if defined(_WIN32) || defined(HAVE_PCAP_VERSION)
2646         extern char pcap_version[];
2647 #else /* defined(_WIN32) || defined(HAVE_PCAP_VERSION) */
2648         static char pcap_version[] = "unknown";
2649 #endif /* defined(_WIN32) || defined(HAVE_PCAP_VERSION) */
2650 #endif /* HAVE_PCAP_LIB_VERSION */
2651         const char *smi_version_string;
2652
2653 #ifdef HAVE_PCAP_LIB_VERSION
2654 #ifdef _WIN32
2655         (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
2656 #else /* _WIN32 */
2657         (void)fprintf(stderr, "%s version %s\n", program_name, version);
2658 #endif /* _WIN32 */
2659         (void)fprintf(stderr, "%s\n",pcap_lib_version());
2660 #else /* HAVE_PCAP_LIB_VERSION */
2661 #ifdef _WIN32
2662         (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
2663         (void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version);
2664 #else /* _WIN32 */
2665         (void)fprintf(stderr, "%s version %s\n", program_name, version);
2666         (void)fprintf(stderr, "libpcap version %s\n", pcap_version);
2667 #endif /* _WIN32 */
2668 #endif /* HAVE_PCAP_LIB_VERSION */
2669
2670 #if defined(HAVE_LIBCRYPTO) && defined(SSLEAY_VERSION)
2671         (void)fprintf (stderr, "%s\n", SSLeay_version(SSLEAY_VERSION));
2672 #endif
2673
2674         smi_version_string = nd_smi_version_string();
2675         if (smi_version_string != NULL)
2676                 (void)fprintf (stderr, "SMI-library: %s\n", smi_version_string);
2677 }
2678 USES_APPLE_RST
2679
2680 static void
2681 print_usage(void)
2682 {
2683         print_version();
2684         (void)fprintf(stderr,
2685 "Usage: %s [-aAbd" D_FLAG "efhH" I_FLAG J_FLAG "KlLnNOpqStu" U_FLAG "vxX#]" B_FLAG_USAGE " [ -c count ]\n", program_name);
2686         (void)fprintf(stderr,
2687 "\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n");
2688         (void)fprintf(stderr,
2689 "\t\t[ -i interface ]" j_FLAG_USAGE " [ -M secret ] [ --number ]\n");
2690 #ifdef HAVE_PCAP_SETDIRECTION
2691         (void)fprintf(stderr,
2692 "\t\t[ -Q in|out|inout ]\n");
2693 #endif
2694         (void)fprintf(stderr,
2695 "\t\t[ -r file ] [ -s snaplen ] ");
2696 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
2697         (void)fprintf(stderr, "[ --time-stamp-precision precision ]\n");
2698         (void)fprintf(stderr,
2699 "\t\t");
2700 #endif
2701 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
2702         (void)fprintf(stderr, "[ --immediate-mode ] ");
2703 #endif
2704         (void)fprintf(stderr, "[ -T type ] [ --version ] [ -V file ]\n");
2705         (void)fprintf(stderr,
2706 "\t\t[ -w file ] [ -W filecount ] [ -y datalinktype ] [ -z postrotate-command ]\n");
2707         (void)fprintf(stderr,
2708 "\t\t[ -Z user ] [ expression ]\n");
2709 }
2710 /*
2711  * Local Variables:
2712  * c-style: whitesmith
2713  * c-basic-offset: 8
2714  * End:
2715  */