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 static const char rcsid[] _U_ =
  33     "@(#) $Header: /tcpdump/master/tcpdump/tcpdump.c,v 1.283 2008-09-25 21:45:50 guy Exp $ (LBL)";
  34 #endif
  35
  36 /*
  37  * tcpdump - monitor tcp/ip traffic on an ethernet.
  38  *
  39  * First written in 1987 by Van Jacobson, Lawrence Berkeley Laboratory.
  40  * Mercilessly hacked and occasionally improved since then via the
  41  * combined efforts of Van, Steve McCanne and Craig Leres of LBL.
  42  */
  43
  44 #ifdef HAVE_CONFIG_H
  45 #include "config.h"
  46 #endif
  47
  48 #include <tcpdump-stdinc.h>
  49
  50 #ifdef WIN32
  51 #include "getopt.h"
  52 #include "w32_fzs.h"
  53 extern int strcasecmp (const char *__s1, const char *__s2);
  54 extern int SIZE_BUF;
  55 #define off_t long
  56 #define uint UINT
  57 #endif /* WIN32 */
  58
  59 #ifdef HAVE_SMI_H
  60 #include <smi.h>
  61 #endif
  62
  63 #include <pcap.h>
  64 #include <signal.h>
  65 #include <stdio.h>
  66 #include <stdlib.h>
  67 #include <string.h>
  68 #include <limits.h>
  69 #ifndef WIN32
  70 #include <sys/wait.h>
  71 #include <sys/resource.h>
  72 #include <pwd.h>
  73 #include <grp.h>
  74 #include <errno.h>
  75 #endif /* WIN32 */
  76
  77
  78 #include "netdissect.h"
  79 #include "interface.h"
  80 #include "addrtoname.h"
  81 #include "machdep.h"
  82 #include "setsignal.h"
  83 #include "gmt2local.h"
  84 #include "pcap-missing.h"
  85
  86 #ifndef NAME_MAX
  87 #define NAME_MAX 255
  88 #endif
  89
  90 netdissect_options Gndo;
  91 netdissect_options *gndo = &Gndo;
  92
  93 static int dflag;                       /* print filter code */
  94 static int Lflag;                       /* list available data link types and exit */
  95 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
  96 static int Jflag;                       /* list available time stamp types */
  97 #endif
  98 static char *zflag = NULL;              /* compress each savefile using a specified command (like gzip or bzip2) */
  99
 100 static int infodelay;
 101 static int infoprint;
 102
 103 char *program_name;
 104
 105 int32_t thiszone;               /* seconds offset from gmt to local time */
 106
 107 /* Forwards */
 108 static RETSIGTYPE cleanup(int);
 109 static RETSIGTYPE child_cleanup(int);
 110 static void usage(void) __attribute__((noreturn));
 111 static void show_dlts_and_exit(const char *device, pcap_t *pd) __attribute__((noreturn));
 112
 113 static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
 114 static void ndo_default_print(netdissect_options *, const u_char *, u_int);
 115 static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *);
 116 static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
 117 static void droproot(const char *, const char *);
 118 static void ndo_error(netdissect_options *ndo, const char *fmt, ...)
 119      __attribute__ ((noreturn, format (printf, 2, 3)));
 120 static void ndo_warning(netdissect_options *ndo, const char *fmt, ...);
 121
 122 #ifdef SIGINFO
 123 RETSIGTYPE requestinfo(int);
 124 #endif
 125
 126 #if defined(USE_WIN32_MM_TIMER)
 127   #include <MMsystem.h>
 128   static UINT timer_id;
 129   static void CALLBACK verbose_stats_dump(UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR);
 130 #elif defined(HAVE_ALARM)
 131   static void verbose_stats_dump(int sig);
 132 #endif
 133
 134 static void info(int);
 135 static u_int packets_captured;
 136
 137 struct printer {
 138         if_printer f;
 139         int type;
 140 };
 141
 142
 143 struct ndo_printer {
 144         if_ndo_printer f;
 145         int type;
 146 };
 147
 148
 149 static struct printer printers[] = {
 150         { arcnet_if_print,      DLT_ARCNET },
 151 #ifdef DLT_ARCNET_LINUX
 152         { arcnet_linux_if_print, DLT_ARCNET_LINUX },
 153 #endif
 154         { token_if_print,       DLT_IEEE802 },
 155 #ifdef DLT_LANE8023
 156         { lane_if_print,        DLT_LANE8023 },
 157 #endif
 158 #ifdef DLT_CIP
 159         { cip_if_print,         DLT_CIP },
 160 #endif
 161 #ifdef DLT_ATM_CLIP
 162         { cip_if_print,         DLT_ATM_CLIP },
 163 #endif
 164         { sl_if_print,          DLT_SLIP },
 165 #ifdef DLT_SLIP_BSDOS
 166         { sl_bsdos_if_print,    DLT_SLIP_BSDOS },
 167 #endif
 168         { ppp_if_print,         DLT_PPP },
 169 #ifdef DLT_PPP_WITHDIRECTION
 170         { ppp_if_print,         DLT_PPP_WITHDIRECTION },
 171 #endif
 172 #ifdef DLT_PPP_BSDOS
 173         { ppp_bsdos_if_print,   DLT_PPP_BSDOS },
 174 #endif
 175         { fddi_if_print,        DLT_FDDI },
 176         { null_if_print,        DLT_NULL },
 177 #ifdef DLT_LOOP
 178         { null_if_print,        DLT_LOOP },
 179 #endif
 180         { raw_if_print,         DLT_RAW },
 181         { atm_if_print,         DLT_ATM_RFC1483 },
 182 #ifdef DLT_C_HDLC
 183         { chdlc_if_print,       DLT_C_HDLC },
 184 #endif
 185 #ifdef DLT_HDLC
 186         { chdlc_if_print,       DLT_HDLC },
 187 #endif
 188 #ifdef DLT_PPP_SERIAL
 189         { ppp_hdlc_if_print,    DLT_PPP_SERIAL },
 190 #endif
 191 #ifdef DLT_PPP_ETHER
 192         { pppoe_if_print,       DLT_PPP_ETHER },
 193 #endif
 194 #ifdef DLT_LINUX_SLL
 195         { sll_if_print,         DLT_LINUX_SLL },
 196 #endif
 197 #ifdef DLT_IEEE802_11
 198         { ieee802_11_if_print,  DLT_IEEE802_11},
 199 #endif
 200 #ifdef DLT_LTALK
 201         { ltalk_if_print,       DLT_LTALK },
 202 #endif
 203 #if defined(DLT_PFLOG) && defined(HAVE_NET_PFVAR_H)
 204         { pflog_if_print,       DLT_PFLOG },
 205 #endif
 206 #ifdef DLT_FR
 207         { fr_if_print,          DLT_FR },
 208 #endif
 209 #ifdef DLT_FRELAY
 210         { fr_if_print,          DLT_FRELAY },
 211 #endif
 212 #ifdef DLT_SUNATM
 213         { sunatm_if_print,      DLT_SUNATM },
 214 #endif
 215 #ifdef DLT_IP_OVER_FC
 216         { ipfc_if_print,        DLT_IP_OVER_FC },
 217 #endif
 218 #ifdef DLT_PRISM_HEADER
 219         { prism_if_print,       DLT_PRISM_HEADER },
 220 #endif
 221 #ifdef DLT_IEEE802_11_RADIO
 222         { ieee802_11_radio_if_print,    DLT_IEEE802_11_RADIO },
 223 #endif
 224 #ifdef DLT_ENC
 225         { enc_if_print,         DLT_ENC },
 226 #endif
 227 #ifdef DLT_SYMANTEC_FIREWALL
 228         { symantec_if_print,    DLT_SYMANTEC_FIREWALL },
 229 #endif
 230 #ifdef DLT_APPLE_IP_OVER_IEEE1394
 231         { ap1394_if_print,      DLT_APPLE_IP_OVER_IEEE1394 },
 232 #endif
 233 #ifdef DLT_IEEE802_11_RADIO_AVS
 234         { ieee802_11_radio_avs_if_print,        DLT_IEEE802_11_RADIO_AVS },
 235 #endif
 236 #ifdef DLT_JUNIPER_ATM1
 237         { juniper_atm1_print,   DLT_JUNIPER_ATM1 },
 238 #endif
 239 #ifdef DLT_JUNIPER_ATM2
 240         { juniper_atm2_print,   DLT_JUNIPER_ATM2 },
 241 #endif
 242 #ifdef DLT_JUNIPER_MFR
 243         { juniper_mfr_print,    DLT_JUNIPER_MFR },
 244 #endif
 245 #ifdef DLT_JUNIPER_MLFR
 246         { juniper_mlfr_print,   DLT_JUNIPER_MLFR },
 247 #endif
 248 #ifdef DLT_JUNIPER_MLPPP
 249         { juniper_mlppp_print,  DLT_JUNIPER_MLPPP },
 250 #endif
 251 #ifdef DLT_JUNIPER_PPPOE
 252         { juniper_pppoe_print,  DLT_JUNIPER_PPPOE },
 253 #endif
 254 #ifdef DLT_JUNIPER_PPPOE_ATM
 255         { juniper_pppoe_atm_print, DLT_JUNIPER_PPPOE_ATM },
 256 #endif
 257 #ifdef DLT_JUNIPER_GGSN
 258         { juniper_ggsn_print,   DLT_JUNIPER_GGSN },
 259 #endif
 260 #ifdef DLT_JUNIPER_ES
 261         { juniper_es_print,     DLT_JUNIPER_ES },
 262 #endif
 263 #ifdef DLT_JUNIPER_MONITOR
 264         { juniper_monitor_print, DLT_JUNIPER_MONITOR },
 265 #endif
 266 #ifdef DLT_JUNIPER_SERVICES
 267         { juniper_services_print, DLT_JUNIPER_SERVICES },
 268 #endif
 269 #ifdef DLT_JUNIPER_ETHER
 270         { juniper_ether_print,  DLT_JUNIPER_ETHER },
 271 #endif
 272 #ifdef DLT_JUNIPER_PPP
 273         { juniper_ppp_print,    DLT_JUNIPER_PPP },
 274 #endif
 275 #ifdef DLT_JUNIPER_FRELAY
 276         { juniper_frelay_print, DLT_JUNIPER_FRELAY },
 277 #endif
 278 #ifdef DLT_JUNIPER_CHDLC
 279         { juniper_chdlc_print,  DLT_JUNIPER_CHDLC },
 280 #endif
 281 #ifdef DLT_MFR
 282         { mfr_if_print,         DLT_MFR },
 283 #endif
 284 #if defined(DLT_BLUETOOTH_HCI_H4_WITH_PHDR) && defined(HAVE_PCAP_BLUETOOTH_H)
 285         { bt_if_print,          DLT_BLUETOOTH_HCI_H4_WITH_PHDR},
 286 #endif
 287 #ifdef HAVE_PCAP_USB_H
 288 #ifdef DLT_USB_LINUX
 289         { usb_linux_48_byte_print, DLT_USB_LINUX},
 290 #endif /* DLT_USB_LINUX */
 291 #ifdef DLT_USB_LINUX_MMAPPED
 292         { usb_linux_64_byte_print, DLT_USB_LINUX_MMAPPED},
 293 #endif /* DLT_USB_LINUX_MMAPPED */
 294 #endif /* HAVE_PCAP_USB_H */
 295 #ifdef DLT_IPV4
 296         { raw_if_print,         DLT_IPV4 },
 297 #endif
 298 #ifdef DLT_IPV6
 299         { raw_if_print,         DLT_IPV6 },
 300 #endif
 301         { NULL,                 0 },
 302 };
 303
 304 static struct ndo_printer ndo_printers[] = {
 305         { ether_if_print,       DLT_EN10MB },
 306 #ifdef DLT_IPNET
 307         { ipnet_if_print,       DLT_IPNET },
 308 #endif
 309 #ifdef DLT_IEEE802_15_4
 310         { ieee802_15_4_if_print, DLT_IEEE802_15_4 },
 311 #endif
 312 #ifdef DLT_IEEE802_15_4_NOFCS
 313         { ieee802_15_4_if_print, DLT_IEEE802_15_4_NOFCS },
 314 #endif
 315 #ifdef DLT_PPI
 316         { ppi_if_print,         DLT_PPI },
 317 #endif
 318 #ifdef DLT_NETANALYZER
 319         { netanalyzer_if_print, DLT_NETANALYZER },
 320 #endif
 321 #ifdef DLT_NETANALYZER_TRANSPARENT
 322         { netanalyzer_transparent_if_print, DLT_NETANALYZER_TRANSPARENT },
 323 #endif
 324         { NULL,                 0 },
 325 };
 326
 327 if_printer
 328 lookup_printer(int type)
 329 {
 330         struct printer *p;
 331
 332         for (p = printers; p->f; ++p)
 333                 if (type == p->type)
 334                         return p->f;
 335
 336         return NULL;
 337         /* NOTREACHED */
 338 }
 339
 340 if_ndo_printer
 341 lookup_ndo_printer(int type)
 342 {
 343         struct ndo_printer *p;
 344
 345         for (p = ndo_printers; p->f; ++p)
 346                 if (type == p->type)
 347                         return p->f;
 348
 349         return NULL;
 350         /* NOTREACHED */
 351 }
 352
 353 static pcap_t *pd;
 354
 355 static int supports_monitor_mode;
 356
 357 extern int optind;
 358 extern int opterr;
 359 extern char *optarg;
 360
 361 struct print_info {
 362         netdissect_options *ndo;
 363         union {
 364                 if_printer     printer;
 365                 if_ndo_printer ndo_printer;
 366         } p;
 367         int ndo_type;
 368 };
 369
 370 struct dump_info {
 371         char    *WFileName;
 372         char    *CurrentFileName;
 373         pcap_t  *pd;
 374         pcap_dumper_t *p;
 375 };
 376
 377 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
 378 static void
 379 show_tstamp_types_and_exit(const char *device, pcap_t *pd)
 380 {
 381         int n_tstamp_types;
 382         int *tstamp_types = 0;
 383         const char *tstamp_type_name;
 384         int i;
 385
 386         n_tstamp_types = pcap_list_tstamp_types(pd, &tstamp_types);
 387         if (n_tstamp_types < 0)
 388                 error("%s", pcap_geterr(pd));
 389
 390         if (n_tstamp_types == 0) {
 391                 fprintf(stderr, "Time stamp type cannot be set for %s\n",
 392                     device);
 393                 exit(0);
 394         }
 395         fprintf(stderr, "Time stamp types for %s (use option -j to set):\n",
 396             device);
 397         for (i = 0; i < n_tstamp_types; i++) {
 398                 tstamp_type_name = pcap_tstamp_type_val_to_name(tstamp_types[i]);
 399                 if (tstamp_type_name != NULL) {
 400                         (void) fprintf(stderr, "  %s (%s)\n", tstamp_type_name,
 401                             pcap_tstamp_type_val_to_description(tstamp_types[i]));
 402                 } else {
 403                         (void) fprintf(stderr, "  %d\n", tstamp_types[i]);
 404                 }
 405         }
 406         pcap_free_tstamp_types(tstamp_types);
 407         exit(0);
 408 }
 409 #endif
 410
 411 static void
 412 show_dlts_and_exit(const char *device, pcap_t *pd)
 413 {
 414         int n_dlts;
 415         int *dlts = 0;
 416         const char *dlt_name;
 417
 418         n_dlts = pcap_list_datalinks(pd, &dlts);
 419         if (n_dlts < 0)
 420                 error("%s", pcap_geterr(pd));
 421         else if (n_dlts == 0 || !dlts)
 422                 error("No data link types.");
 423
 424         /*
 425          * If the interface is known to support monitor mode, indicate
 426          * whether these are the data link types available when not in
 427          * monitor mode, if -I wasn't specified, or when in monitor mode,
 428          * when -I was specified (the link-layer types available in
 429          * monitor mode might be different from the ones available when
 430          * not in monitor mode).
 431          */
 432         if (supports_monitor_mode)
 433                 (void) fprintf(stderr, "Data link types for %s %s (use option -y to set):\n",
 434                     device,
 435                     Iflag ? "when in monitor mode" : "when not in monitor mode");
 436         else
 437                 (void) fprintf(stderr, "Data link types for %s (use option -y to set):\n",
 438                     device);
 439
 440         while (--n_dlts >= 0) {
 441                 dlt_name = pcap_datalink_val_to_name(dlts[n_dlts]);
 442                 if (dlt_name != NULL) {
 443                         (void) fprintf(stderr, "  %s (%s)", dlt_name,
 444                             pcap_datalink_val_to_description(dlts[n_dlts]));
 445
 446                         /*
 447                          * OK, does tcpdump handle that type?
 448                          */
 449                         if (lookup_printer(dlts[n_dlts]) == NULL
 450                             && lookup_ndo_printer(dlts[n_dlts]) == NULL)
 451                                 (void) fprintf(stderr, " (printing not supported)");
 452                         fprintf(stderr, "\n");
 453                 } else {
 454                         (void) fprintf(stderr, "  DLT %d (printing not supported)\n",
 455                             dlts[n_dlts]);
 456                 }
 457         }
 458         pcap_free_datalinks(dlts);
 459         exit(0);
 460 }
 461
 462 /*
 463  * Set up flags that might or might not be supported depending on the
 464  * version of libpcap we're using.
 465  */
 466 #if defined(HAVE_PCAP_CREATE) || defined(WIN32)
 467 #define B_FLAG          "B:"
 468 #define B_FLAG_USAGE    " [ -B size ]"
 469 #else /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
 470 #define B_FLAG
 471 #define B_FLAG_USAGE
 472 #endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
 473
 474 #ifdef HAVE_PCAP_CREATE
 475 #define I_FLAG          "I"
 476 #else /* HAVE_PCAP_CREATE */
 477 #define I_FLAG
 478 #endif /* HAVE_PCAP_CREATE */
 479
 480 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
 481 #define j_FLAG          "j:"
 482 #define j_FLAG_USAGE    " [ -j tstamptype ]"
 483 #define J_FLAG          "J"
 484 #else /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
 485 #define j_FLAG
 486 #define j_FLAG_USAGE
 487 #define J_FLAG
 488 #endif /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
 489
 490 #ifdef HAVE_PCAP_FINDALLDEVS
 491 #ifndef HAVE_PCAP_IF_T
 492 #undef HAVE_PCAP_FINDALLDEVS
 493 #endif
 494 #endif
 495
 496 #ifdef HAVE_PCAP_FINDALLDEVS
 497 #define D_FLAG  "D"
 498 #else
 499 #define D_FLAG
 500 #endif
 501
 502 #ifdef HAVE_PCAP_DUMP_FLUSH
 503 #define U_FLAG  "U"
 504 #else
 505 #define U_FLAG
 506 #endif
 507
 508 #ifndef WIN32
 509 /* Drop root privileges and chroot if necessary */
 510 static void
 511 droproot(const char *username, const char *chroot_dir)
 512 {
 513         struct passwd *pw = NULL;
 514
 515         if (chroot_dir && !username) {
 516                 fprintf(stderr, "tcpdump: Chroot without dropping root is insecure\n");
 517                 exit(1);
 518         }
 519
 520         pw = getpwnam(username);
 521         if (pw) {
 522                 if (chroot_dir) {
 523                         if (chroot(chroot_dir) != 0 || chdir ("/") != 0) {
 524                                 fprintf(stderr, "tcpdump: Couldn't chroot/chdir to '%.64s': %s\n",
 525                                     chroot_dir, pcap_strerror(errno));
 526                                 exit(1);
 527                         }
 528                 }
 529                 if (initgroups(pw->pw_name, pw->pw_gid) != 0 ||
 530                     setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) {
 531                         fprintf(stderr, "tcpdump: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n",
 532                             username,
 533                             (unsigned long)pw->pw_uid,
 534                             (unsigned long)pw->pw_gid,
 535                             pcap_strerror(errno));
 536                         exit(1);
 537                 }
 538         }
 539         else {
 540                 fprintf(stderr, "tcpdump: Couldn't find user '%.32s'\n",
 541                     username);
 542                 exit(1);
 543         }
 544 }
 545 #endif /* WIN32 */
 546
 547 static int
 548 getWflagChars(int x)
 549 {
 550         int c = 0;
 551
 552         x -= 1;
 553         while (x > 0) {
 554                 c += 1;
 555                 x /= 10;
 556         }
 557
 558         return c;
 559 }
 560
 561
 562 static void
 563 MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars)
 564 {
 565         char *filename = malloc(NAME_MAX + 1);
 566
 567         /* Process with strftime if Gflag is set. */
 568         if (Gflag != 0) {
 569           struct tm *local_tm;
 570
 571           /* Convert Gflag_time to a usable format */
 572           if ((local_tm = localtime(&Gflag_time)) == NULL) {
 573                   error("MakeTimedFilename: localtime");
 574           }
 575
 576           /* There's no good way to detect an error in strftime since a return
 577            * value of 0 isn't necessarily failure.
 578            */
 579           strftime(filename, NAME_MAX, orig_name, local_tm);
 580         } else {
 581           strncpy(filename, orig_name, NAME_MAX);
 582         }
 583
 584         if (cnt == 0 && max_chars == 0)
 585                 strncpy(buffer, filename, NAME_MAX + 1);
 586         else
 587                 if (snprintf(buffer, NAME_MAX + 1, "%s%0*d", filename, max_chars, cnt) > NAME_MAX)
 588                   /* Report an error if the filename is too large */
 589                   error("too many output files or filename is too long (> %d)", NAME_MAX);
 590         free(filename);
 591 }
 592
 593 static int tcpdump_printf(netdissect_options *ndo _U_,
 594                           const char *fmt, ...)
 595 {
 596
 597   va_list args;
 598   int ret;
 599
 600   va_start(args, fmt);
 601   ret=vfprintf(stdout, fmt, args);
 602   va_end(args);
 603
 604   return ret;
 605 }
 606
 607 int
 608 main(int argc, char **argv)
 609 {
 610         register int cnt, op, i;
 611         bpf_u_int32 localnet, netmask;
 612         register char *cp, *infile, *cmdbuf, *device, *RFileName, *WFileName;
 613         pcap_handler callback;
 614         int type;
 615         struct bpf_program fcode;
 616 #ifndef WIN32
 617         RETSIGTYPE (*oldhandler)(int);
 618 #endif
 619         struct print_info printinfo;
 620         struct dump_info dumpinfo;
 621         u_char *pcap_userdata;
 622         char ebuf[PCAP_ERRBUF_SIZE];
 623         char *username = NULL;
 624         char *chroot_dir = NULL;
 625 #ifdef HAVE_PCAP_FINDALLDEVS
 626         pcap_if_t *devpointer;
 627         int devnum;
 628 #endif
 629         int status;
 630 #ifdef WIN32
 631         if(wsockinit() != 0) return 1;
 632 #endif /* WIN32 */
 633
 634         jflag=-1;       /* not set */
 635         gndo->ndo_Oflag=1;
 636         gndo->ndo_Rflag=1;
 637         gndo->ndo_dlt=-1;
 638         gndo->ndo_default_print=ndo_default_print;
 639         gndo->ndo_printf=tcpdump_printf;
 640         gndo->ndo_error=ndo_error;
 641         gndo->ndo_warning=ndo_warning;
 642         gndo->ndo_snaplen = DEFAULT_SNAPLEN;
 643
 644         cnt = -1;
 645         device = NULL;
 646         infile = NULL;
 647         RFileName = NULL;
 648         WFileName = NULL;
 649         if ((cp = strrchr(argv[0], '/')) != NULL)
 650                 program_name = cp + 1;
 651         else
 652                 program_name = argv[0];
 653
 654         if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
 655                 error("%s", ebuf);
 656
 657 #ifdef LIBSMI
 658         smiInit("tcpdump");
 659 #endif
 660
 661         while (
 662             (op = getopt(argc, argv, "aAb" B_FLAG "c:C:d" D_FLAG "eE:fF:G:hHi:" I_FLAG j_FLAG J_FLAG "KlLm:M:nNOpqr:Rs:StT:u" U_FLAG "vw:W:xXy:Yz:Z:")) != -1)
 663                 switch (op) {
 664
 665                 case 'a':
 666                         /* compatibility for old -a */
 667                         break;
 668
 669                 case 'A':
 670                         ++Aflag;
 671                         break;
 672
 673                 case 'b':
 674                         ++bflag;
 675                         break;
 676
 677 #if defined(HAVE_PCAP_CREATE) || defined(WIN32)
 678                 case 'B':
 679                         Bflag = atoi(optarg)*1024;
 680                         if (Bflag <= 0)
 681                                 error("invalid packet buffer size %s", optarg);
 682                         break;
 683 #endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
 684
 685                 case 'c':
 686                         cnt = atoi(optarg);
 687                         if (cnt <= 0)
 688                                 error("invalid packet count %s", optarg);
 689                         break;
 690
 691                 case 'C':
 692                         Cflag = atoi(optarg) * 1000000;
 693                         if (Cflag < 0)
 694                                 error("invalid file size %s", optarg);
 695                         break;
 696
 697                 case 'd':
 698                         ++dflag;
 699                         break;
 700
 701 #ifdef HAVE_PCAP_FINDALLDEVS
 702                 case 'D':
 703                         if (pcap_findalldevs(&devpointer, ebuf) < 0)
 704                                 error("%s", ebuf);
 705                         else {
 706                                 for (i = 0; devpointer != 0; i++) {
 707                                         printf("%d.%s", i+1, devpointer->name);
 708                                         if (devpointer->description != NULL)
 709                                                 printf(" (%s)", devpointer->description);
 710                                         printf("\n");
 711                                         devpointer = devpointer->next;
 712                                 }
 713                         }
 714                         return 0;
 715 #endif /* HAVE_PCAP_FINDALLDEVS */
 716
 717                 case 'L':
 718                         Lflag++;
 719                         break;
 720
 721                 case 'e':
 722                         ++eflag;
 723                         break;
 724
 725                 case 'E':
 726 #ifndef HAVE_LIBCRYPTO
 727                         warning("crypto code not compiled in");
 728 #endif
 729                         gndo->ndo_espsecret = optarg;
 730                         break;
 731
 732                 case 'f':
 733                         ++fflag;
 734                         break;
 735
 736                 case 'F':
 737                         infile = optarg;
 738                         break;
 739
 740                 case 'G':
 741                         Gflag = atoi(optarg);
 742                         if (Gflag < 0)
 743                                 error("invalid number of seconds %s", optarg);
 744
 745                         /* We will create one file initially. */
 746                         Gflag_count = 0;
 747
 748                         /* Grab the current time for rotation use. */
 749                         if ((Gflag_time = time(NULL)) == (time_t)-1) {
 750                                 error("main: can't get current time: %s",
 751                                     pcap_strerror(errno));
 752                         }
 753                         break;
 754
 755                 case 'h':
 756                         usage();
 757                         break;
 758
 759                 case 'H':
 760                         ++Hflag;
 761                         break;
 762
 763                 case 'i':
 764                         if (optarg[0] == '0' && optarg[1] == 0)
 765                                 error("Invalid adapter index");
 766
 767 #ifdef HAVE_PCAP_FINDALLDEVS
 768                         /*
 769                          * If the argument is a number, treat it as
 770                          * an index into the list of adapters, as
 771                          * printed by "tcpdump -D".
 772                          *
 773                          * This should be OK on UNIX systems, as interfaces
 774                          * shouldn't have names that begin with digits.
 775                          * It can be useful on Windows, where more than
 776                          * one interface can have the same name.
 777                          */
 778                         if ((devnum = atoi(optarg)) != 0) {
 779                                 if (devnum < 0)
 780                                         error("Invalid adapter index");
 781
 782                                 if (pcap_findalldevs(&devpointer, ebuf) < 0)
 783                                         error("%s", ebuf);
 784                                 else {
 785                                         /*
 786                                          * Look for the devnum-th entry
 787                                          * in the list of devices
 788                                          * (1-based).
 789                                          */
 790                                         for (i = 0;
 791                                             i < devnum-1 && devpointer != NULL;
 792                                             i++, devpointer = devpointer->next)
 793                                                 ;
 794                                         if (devpointer == NULL)
 795                                                 error("Invalid adapter index");
 796                                 }
 797                                 device = devpointer->name;
 798                                 break;
 799                         }
 800 #endif /* HAVE_PCAP_FINDALLDEVS */
 801                         device = optarg;
 802                         break;
 803
 804 #ifdef HAVE_PCAP_CREATE
 805                 case 'I':
 806                         ++Iflag;
 807                         break;
 808 #endif /* HAVE_PCAP_CREATE */
 809
 810 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
 811                 case 'j':
 812                         jflag = pcap_tstamp_type_name_to_val(optarg);
 813                         if (jflag < 0)
 814                                 error("invalid time stamp type %s", optarg);
 815                         break;
 816
 817                 case 'J':
 818                         Jflag++;
 819                         break;
 820 #endif
 821
 822                 case 'l':
 823 #ifdef WIN32
 824                         /*
 825                          * _IOLBF is the same as _IOFBF in Microsoft's C
 826                          * libraries; the only alternative they offer
 827                          * is _IONBF.
 828                          *
 829                          * XXX - this should really be checking for MSVC++,
 830                          * not WIN32, if, for example, MinGW has its own
 831                          * C library that is more UNIX-compatible.
 832                          */
 833                         setvbuf(stdout, NULL, _IONBF, 0);
 834 #else /* WIN32 */
 835 #ifdef HAVE_SETLINEBUF
 836                         setlinebuf(stdout);
 837 #else
 838                         setvbuf(stdout, NULL, _IOLBF, 0);
 839 #endif
 840 #endif /* WIN32 */
 841                         break;
 842
 843                 case 'K':
 844                         ++Kflag;
 845                         break;
 846
 847                 case 'm':
 848 #ifdef LIBSMI
 849                         if (smiLoadModule(optarg) == 0) {
 850                                 error("could not load MIB module %s", optarg);
 851                         }
 852                         sflag = 1;
 853 #else
 854                         (void)fprintf(stderr, "%s: ignoring option `-m %s' ",
 855                                       program_name, optarg);
 856                         (void)fprintf(stderr, "(no libsmi support)\n");
 857 #endif
 858                         break;
 859
 860                 case 'M':
 861                         /* TCP-MD5 shared secret */
 862 #ifndef HAVE_LIBCRYPTO
 863                         warning("crypto code not compiled in");
 864 #endif
 865                         sigsecret = optarg;
 866                         break;
 867
 868                 case 'n':
 869                         ++nflag;
 870                         break;
 871
 872                 case 'N':
 873                         ++Nflag;
 874                         break;
 875
 876                 case 'O':
 877                         Oflag = 0;
 878                         break;
 879
 880                 case 'p':
 881                         ++pflag;
 882                         break;
 883
 884                 case 'q':
 885                         ++qflag;
 886                         ++suppress_default_print;
 887                         break;
 888
 889                 case 'r':
 890                         RFileName = optarg;
 891                         break;
 892
 893                 case 'R':
 894                         Rflag = 0;
 895                         break;
 896
 897                 case 's': {
 898                         char *end;
 899
 900                         snaplen = strtol(optarg, &end, 0);
 901                         if (optarg == end || *end != '\0'
 902                             || snaplen < 0 || snaplen > MAXIMUM_SNAPLEN)
 903                                 error("invalid snaplen %s", optarg);
 904                         else if (snaplen == 0)
 905                                 snaplen = MAXIMUM_SNAPLEN;
 906                         break;
 907                 }
 908
 909                 case 'S':
 910                         ++Sflag;
 911                         break;
 912
 913                 case 't':
 914                         ++tflag;
 915                         break;
 916
 917                 case 'T':
 918                         if (strcasecmp(optarg, "vat") == 0)
 919                                 packettype = PT_VAT;
 920                         else if (strcasecmp(optarg, "wb") == 0)
 921                                 packettype = PT_WB;
 922                         else if (strcasecmp(optarg, "rpc") == 0)
 923                                 packettype = PT_RPC;
 924                         else if (strcasecmp(optarg, "rtp") == 0)
 925                                 packettype = PT_RTP;
 926                         else if (strcasecmp(optarg, "rtcp") == 0)
 927                                 packettype = PT_RTCP;
 928                         else if (strcasecmp(optarg, "snmp") == 0)
 929                                 packettype = PT_SNMP;
 930                         else if (strcasecmp(optarg, "cnfp") == 0)
 931                                 packettype = PT_CNFP;
 932                         else if (strcasecmp(optarg, "tftp") == 0)
 933                                 packettype = PT_TFTP;
 934                         else if (strcasecmp(optarg, "aodv") == 0)
 935                                 packettype = PT_AODV;
 936                         else if (strcasecmp(optarg, "carp") == 0)
 937                                 packettype = PT_CARP;
 938                         else
 939                                 error("unknown packet type `%s'", optarg);
 940                         break;
 941
 942                 case 'u':
 943                         ++uflag;
 944                         break;
 945
 946 #ifdef HAVE_PCAP_DUMP_FLUSH
 947                 case 'U':
 948                         ++Uflag;
 949                         break;
 950 #endif
 951
 952                 case 'v':
 953                         ++vflag;
 954                         break;
 955
 956                 case 'w':
 957                         WFileName = optarg;
 958                         break;
 959
 960                 case 'W':
 961                         Wflag = atoi(optarg);
 962                         if (Wflag < 0)
 963                                 error("invalid number of output files %s", optarg);
 964                         WflagChars = getWflagChars(Wflag);
 965                         break;
 966
 967                 case 'x':
 968                         ++xflag;
 969                         ++suppress_default_print;
 970                         break;
 971
 972                 case 'X':
 973                         ++Xflag;
 974                         ++suppress_default_print;
 975                         break;
 976
 977                 case 'y':
 978                         gndo->ndo_dltname = optarg;
 979                         gndo->ndo_dlt =
 980                           pcap_datalink_name_to_val(gndo->ndo_dltname);
 981                         if (gndo->ndo_dlt < 0)
 982                                 error("invalid data link type %s", gndo->ndo_dltname);
 983                         break;
 984
 985 #if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
 986                 case 'Y':
 987                         {
 988                         /* Undocumented flag */
 989 #ifdef HAVE_PCAP_DEBUG
 990                         extern int pcap_debug;
 991                         pcap_debug = 1;
 992 #else
 993                         extern int yydebug;
 994                         yydebug = 1;
 995 #endif
 996                         }
 997                         break;
 998 #endif
 999                 case 'z':
1000                         if (optarg) {
1001                                 zflag = strdup(optarg);
1002                         } else {
1003                                 usage();
1004                                 /* NOTREACHED */
1005                         }
1006                         break;
1007
1008                 case 'Z':
1009                         if (optarg) {
1010                                 username = strdup(optarg);
1011                         }
1012                         else {
1013                                 usage();
1014                                 /* NOTREACHED */
1015                         }
1016                         break;
1017
1018                 default:
1019                         usage();
1020                         /* NOTREACHED */
1021                 }
1022
1023         switch (tflag) {
1024
1025         case 0: /* Default */
1026         case 4: /* Default + Date*/
1027                 thiszone = gmt2local(0);
1028                 break;
1029
1030         case 1: /* No time stamp */
1031         case 2: /* Unix timeval style */
1032         case 3: /* Microseconds since previous packet */
1033         case 5: /* Microseconds since first packet */
1034                 break;
1035
1036         default: /* Not supported */
1037                 error("only -t, -tt, -ttt, -tttt and -ttttt are supported");
1038                 break;
1039         }
1040
1041 #ifdef WITH_CHROOT
1042         /* if run as root, prepare for chrooting */
1043         if (getuid() == 0 || geteuid() == 0) {
1044                 /* future extensibility for cmd-line arguments */
1045                 if (!chroot_dir)
1046                         chroot_dir = WITH_CHROOT;
1047         }
1048 #endif
1049
1050 #ifdef WITH_USER
1051         /* if run as root, prepare for dropping root privileges */
1052         if (getuid() == 0 || geteuid() == 0) {
1053                 /* Run with '-Z root' to restore old behaviour */
1054                 if (!username)
1055                         username = WITH_USER;
1056         }
1057 #endif
1058
1059         if (RFileName != NULL) {
1060                 int dlt;
1061                 const char *dlt_name;
1062
1063 #ifndef WIN32
1064                 /*
1065                  * We don't need network access, so relinquish any set-UID
1066                  * or set-GID privileges we have (if any).
1067                  *
1068                  * We do *not* want set-UID privileges when opening a
1069                  * trace file, as that might let the user read other
1070                  * people's trace files (especially if we're set-UID
1071                  * root).
1072                  */
1073                 if (setgid(getgid()) != 0 || setuid(getuid()) != 0 )
1074                         fprintf(stderr, "Warning: setgid/setuid failed !\n");
1075 #endif /* WIN32 */
1076                 pd = pcap_open_offline(RFileName, ebuf);
1077                 if (pd == NULL)
1078                         error("%s", ebuf);
1079                 dlt = pcap_datalink(pd);
1080                 dlt_name = pcap_datalink_val_to_name(dlt);
1081                 if (dlt_name == NULL) {
1082                         fprintf(stderr, "reading from file %s, link-type %u\n",
1083                             RFileName, dlt);
1084                 } else {
1085                         fprintf(stderr,
1086                             "reading from file %s, link-type %s (%s)\n",
1087                             RFileName, dlt_name,
1088                             pcap_datalink_val_to_description(dlt));
1089                 }
1090                 localnet = 0;
1091                 netmask = 0;
1092                 if (fflag != 0)
1093                         error("-f and -r options are incompatible");
1094         } else {
1095                 if (device == NULL) {
1096                         device = pcap_lookupdev(ebuf);
1097                         if (device == NULL)
1098                                 error("%s", ebuf);
1099                 }
1100 #ifdef WIN32
1101                 if(strlen(device) == 1) //we assume that an ASCII string is always longer than 1 char
1102                 {                                               //a Unicode string has a \0 as second byte (so strlen() is 1)
1103                         fprintf(stderr, "%s: listening on %ws\n", program_name, device);
1104                 }
1105                 else
1106                 {
1107                         fprintf(stderr, "%s: listening on %s\n", program_name, device);
1108                 }
1109
1110                 fflush(stderr);
1111 #endif /* WIN32 */
1112 #ifdef HAVE_PCAP_CREATE
1113                 pd = pcap_create(device, ebuf);
1114                 if (pd == NULL)
1115                         error("%s", ebuf);
1116 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
1117                 if (Jflag)
1118                         show_tstamp_types_and_exit(device, pd);
1119 #endif
1120                 /*
1121                  * Is this an interface that supports monitor mode?
1122                  */
1123                 if (pcap_can_set_rfmon(pd) == 1)
1124                         supports_monitor_mode = 1;
1125                 else
1126                         supports_monitor_mode = 0;
1127                 status = pcap_set_snaplen(pd, snaplen);
1128                 if (status != 0)
1129                         error("%s: Can't set snapshot length: %s",
1130                             device, pcap_statustostr(status));
1131                 status = pcap_set_promisc(pd, !pflag);
1132                 if (status != 0)
1133                         error("%s: Can't set promiscuous mode: %s",
1134                             device, pcap_statustostr(status));
1135                 if (Iflag) {
1136                         status = pcap_set_rfmon(pd, 1);
1137                         if (status != 0)
1138                                 error("%s: Can't set monitor mode: %s",
1139                                     device, pcap_statustostr(status));
1140                 }
1141                 status = pcap_set_timeout(pd, 1000);
1142                 if (status != 0)
1143                         error("%s: pcap_set_timeout failed: %s",
1144                             device, pcap_statustostr(status));
1145                 if (Bflag != 0) {
1146                         status = pcap_set_buffer_size(pd, Bflag);
1147                         if (status != 0)
1148                                 error("%s: Can't set buffer size: %s",
1149                                     device, pcap_statustostr(status));
1150                 }
1151 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
1152                 if (jflag != -1) {
1153                         status = pcap_set_tstamp_type(pd, jflag);
1154                         if (status < 0)
1155                                 error("%s: Can't set time stamp type: %s",
1156                                     device, pcap_statustostr(status));
1157                 }
1158 #endif
1159                 status = pcap_activate(pd);
1160                 if (status < 0) {
1161                         /*
1162                          * pcap_activate() failed.
1163                          */
1164                         cp = pcap_geterr(pd);
1165                         if (status == PCAP_ERROR)
1166                                 error("%s", cp);
1167                         else if ((status == PCAP_ERROR_NO_SUCH_DEVICE ||
1168                                   status == PCAP_ERROR_PERM_DENIED) &&
1169                                  *cp != '\0')
1170                                 error("%s: %s\n(%s)", device,
1171                                     pcap_statustostr(status), cp);
1172                         else
1173                                 error("%s: %s", device,
1174                                     pcap_statustostr(status));
1175                 } else if (status > 0) {
1176                         /*
1177                          * pcap_activate() succeeded, but it's warning us
1178                          * of a problem it had.
1179                          */
1180                         cp = pcap_geterr(pd);
1181                         if (status == PCAP_WARNING)
1182                                 warning("%s", cp);
1183                         else if (status == PCAP_WARNING_PROMISC_NOTSUP &&
1184                                  *cp != '\0')
1185                                 warning("%s: %s\n(%s)", device,
1186                                     pcap_statustostr(status), cp);
1187                         else
1188                                 warning("%s: %s", device,
1189                                     pcap_statustostr(status));
1190                 }
1191 #else
1192                 *ebuf = '\0';
1193                 pd = pcap_open_live(device, snaplen, !pflag, 1000, ebuf);
1194                 if (pd == NULL)
1195                         error("%s", ebuf);
1196                 else if (*ebuf)
1197                         warning("%s", ebuf);
1198 #endif /* HAVE_PCAP_CREATE */
1199                 /*
1200                  * Let user own process after socket has been opened.
1201                  */
1202 #ifndef WIN32
1203                 if (setgid(getgid()) != 0 || setuid(getuid()) != 0)
1204                         fprintf(stderr, "Warning: setgid/setuid failed !\n");
1205 #endif /* WIN32 */
1206 #if !defined(HAVE_PCAP_CREATE) && defined(WIN32)
1207                 if(Bflag != 0)
1208                         if(pcap_setbuff(pd, Bflag)==-1){
1209                                 error("%s", pcap_geterr(pd));
1210                         }
1211 #endif /* !defined(HAVE_PCAP_CREATE) && defined(WIN32) */
1212                 if (Lflag)
1213                         show_dlts_and_exit(device, pd);
1214                 if (gndo->ndo_dlt >= 0) {
1215 #ifdef HAVE_PCAP_SET_DATALINK
1216                         if (pcap_set_datalink(pd, gndo->ndo_dlt) < 0)
1217                                 error("%s", pcap_geterr(pd));
1218 #else
1219                         /*
1220                          * We don't actually support changing the
1221                          * data link type, so we only let them
1222                          * set it to what it already is.
1223                          */
1224                         if (gndo->ndo_dlt != pcap_datalink(pd)) {
1225                                 error("%s is not one of the DLTs supported by this device\n",
1226                                       gndo->ndo_dltname);
1227                         }
1228 #endif
1229                         (void)fprintf(stderr, "%s: data link type %s\n",
1230                                       program_name, gndo->ndo_dltname);
1231                         (void)fflush(stderr);
1232                 }
1233                 i = pcap_snapshot(pd);
1234                 if (snaplen < i) {
1235                         warning("snaplen raised from %d to %d", snaplen, i);
1236                         snaplen = i;
1237                 }
1238                 if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
1239                         localnet = 0;
1240                         netmask = 0;
1241                         warning("%s", ebuf);
1242                 }
1243         }
1244         if (infile)
1245                 cmdbuf = read_infile(infile);
1246         else
1247                 cmdbuf = copy_argv(&argv[optind]);
1248
1249         if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
1250                 error("%s", pcap_geterr(pd));
1251         free(cmdbuf);
1252         if (dflag) {
1253                 bpf_dump(&fcode, dflag);
1254                 pcap_close(pd);
1255                 exit(0);
1256         }
1257         init_addrtoname(localnet, netmask);
1258         init_checksum();
1259
1260 #ifndef WIN32
1261         (void)setsignal(SIGPIPE, cleanup);
1262         (void)setsignal(SIGTERM, cleanup);
1263         (void)setsignal(SIGINT, cleanup);
1264 #endif /* WIN32 */
1265 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
1266         (void)setsignal(SIGCHLD, child_cleanup);
1267 #endif
1268         /* Cooperate with nohup(1) */
1269 #ifndef WIN32
1270         if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL)
1271                 (void)setsignal(SIGHUP, oldhandler);
1272 #endif /* WIN32 */
1273
1274 #ifndef WIN32
1275         /*
1276          * If a user name was specified with "-Z", attempt to switch to
1277          * that user's UID.  This would probably be used with sudo,
1278          * to allow tcpdump to be run in a special restricted
1279          * account (if you just want to allow users to open capture
1280          * devices, and can't just give users that permission,
1281          * you'd make tcpdump set-UID or set-GID).
1282          *
1283          * Tcpdump doesn't necessarily write only to one savefile;
1284          * the general only way to allow a -Z instance to write to
1285          * savefiles as the user under whose UID it's run, rather
1286          * than as the user specified with -Z, would thus be to switch
1287          * to the original user ID before opening a capture file and
1288          * then switch back to the -Z user ID after opening the savefile.
1289          * Switching to the -Z user ID only after opening the first
1290          * savefile doesn't handle the general case.
1291          */
1292         if (getuid() == 0 || geteuid() == 0) {
1293                 if (username || chroot_dir)
1294                         droproot(username, chroot_dir);
1295         }
1296 #endif /* WIN32 */
1297
1298         if (pcap_setfilter(pd, &fcode) < 0)
1299                 error("%s", pcap_geterr(pd));
1300         if (WFileName) {
1301                 pcap_dumper_t *p;
1302                 /* Do not exceed the default NAME_MAX for files. */
1303                 dumpinfo.CurrentFileName = (char *)malloc(NAME_MAX + 1);
1304
1305                 if (dumpinfo.CurrentFileName == NULL)
1306                         error("malloc of dumpinfo.CurrentFileName");
1307
1308                 /* We do not need numbering for dumpfiles if Cflag isn't set. */
1309                 if (Cflag != 0)
1310                   MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, WflagChars);
1311                 else
1312                   MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, 0);
1313
1314                 p = pcap_dump_open(pd, dumpinfo.CurrentFileName);
1315                 if (p == NULL)
1316                         error("%s", pcap_geterr(pd));
1317                 if (Cflag != 0 || Gflag != 0) {
1318                         callback = dump_packet_and_trunc;
1319                         dumpinfo.WFileName = WFileName;
1320                         dumpinfo.pd = pd;
1321                         dumpinfo.p = p;
1322                         pcap_userdata = (u_char *)&dumpinfo;
1323                 } else {
1324                         callback = dump_packet;
1325                         pcap_userdata = (u_char *)p;
1326                 }
1327 #ifdef HAVE_PCAP_DUMP_FLUSH
1328                 if (Uflag)
1329                         pcap_dump_flush(p);
1330 #endif
1331         } else {
1332                 type = pcap_datalink(pd);
1333                 printinfo.ndo_type = 1;
1334                 printinfo.ndo = gndo;
1335                 printinfo.p.ndo_printer = lookup_ndo_printer(type);
1336                 if (printinfo.p.ndo_printer == NULL) {
1337                         printinfo.p.printer = lookup_printer(type);
1338                         printinfo.ndo_type = 0;
1339                         if (printinfo.p.printer == NULL) {
1340                                 gndo->ndo_dltname = pcap_datalink_val_to_name(type);
1341                                 if (gndo->ndo_dltname != NULL)
1342                                         error("packet printing is not supported for link type %s: use -w",
1343                                               gndo->ndo_dltname);
1344                                 else
1345                                         error("packet printing is not supported for link type %d: use -w", type);
1346                         }
1347                 }
1348                 callback = print_packet;
1349                 pcap_userdata = (u_char *)&printinfo;
1350         }
1351
1352 #ifdef SIGINFO
1353         /*
1354          * We can't get statistics when reading from a file rather
1355          * than capturing from a device.
1356          */
1357         if (RFileName == NULL)
1358                 (void)setsignal(SIGINFO, requestinfo);
1359 #endif
1360
1361         if (vflag > 0 && WFileName) {
1362                 /*
1363                  * When capturing to a file, "-v" means tcpdump should,
1364                  * every 10 secodns, "v"erbosely report the number of
1365                  * packets captured.
1366                  */
1367 #ifdef USE_WIN32_MM_TIMER
1368                 /* call verbose_stats_dump() each 1000 +/-100msec */
1369                 timer_id = timeSetEvent(1000, 100, verbose_stats_dump, 0, TIME_PERIODIC);
1370                 setvbuf(stderr, NULL, _IONBF, 0);
1371 #elif defined(HAVE_ALARM)
1372                 (void)setsignal(SIGALRM, verbose_stats_dump);
1373                 alarm(1);
1374 #endif
1375         }
1376
1377 #ifndef WIN32
1378         if (RFileName == NULL) {
1379                 int dlt;
1380                 const char *dlt_name;
1381
1382                 if (!vflag && !WFileName) {
1383                         (void)fprintf(stderr,
1384                             "%s: verbose output suppressed, use -v or -vv for full protocol decode\n",
1385                             program_name);
1386                 } else
1387                         (void)fprintf(stderr, "%s: ", program_name);
1388                 dlt = pcap_datalink(pd);
1389                 dlt_name = pcap_datalink_val_to_name(dlt);
1390                 if (dlt_name == NULL) {
1391                         (void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n",
1392                             device, dlt, snaplen);
1393                 } else {
1394                         (void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n",
1395                             device, dlt_name,
1396                             pcap_datalink_val_to_description(dlt), snaplen);
1397                 }
1398                 (void)fflush(stderr);
1399         }
1400 #endif /* WIN32 */
1401         status = pcap_loop(pd, cnt, callback, pcap_userdata);
1402         if (WFileName == NULL) {
1403                 /*
1404                  * We're printing packets.  Flush the printed output,
1405                  * so it doesn't get intermingled with error output.
1406                  */
1407                 if (status == -2) {
1408                         /*
1409                          * We got interrupted, so perhaps we didn't
1410                          * manage to finish a line we were printing.
1411                          * Print an extra newline, just in case.
1412                          */
1413                         putchar('\n');
1414                 }
1415                 (void)fflush(stdout);
1416         }
1417         if (status == -1) {
1418                 /*
1419                  * Error.  Report it.
1420                  */
1421                 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
1422                     program_name, pcap_geterr(pd));
1423         }
1424         if (RFileName == NULL) {
1425                 /*
1426                  * We're doing a live capture.  Report the capture
1427                  * statistics.
1428                  */
1429                 info(1);
1430         }
1431         pcap_close(pd);
1432         exit(status == -1 ? 1 : 0);
1433 }
1434
1435 /* make a clean exit on interrupts */
1436 static RETSIGTYPE
1437 cleanup(int signo _U_)
1438 {
1439 #ifdef USE_WIN32_MM_TIMER
1440         if (timer_id)
1441                 timeKillEvent(timer_id);
1442         timer_id = 0;
1443 #elif defined(HAVE_ALARM)
1444         alarm(0);
1445 #endif
1446
1447 #ifdef HAVE_PCAP_BREAKLOOP
1448         /*
1449          * We have "pcap_breakloop()"; use it, so that we do as little
1450          * as possible in the signal handler (it's probably not safe
1451          * to do anything with standard I/O streams in a signal handler -
1452          * the ANSI C standard doesn't say it is).
1453          */
1454         pcap_breakloop(pd);
1455 #else
1456         /*
1457          * We don't have "pcap_breakloop()"; this isn't safe, but
1458          * it's the best we can do.  Print the summary if we're
1459          * not reading from a savefile - i.e., if we're doing a
1460          * live capture - and exit.
1461          */
1462         if (pd != NULL && pcap_file(pd) == NULL) {
1463                 /*
1464                  * We got interrupted, so perhaps we didn't
1465                  * manage to finish a line we were printing.
1466                  * Print an extra newline, just in case.
1467                  */
1468                 putchar('\n');
1469                 (void)fflush(stdout);
1470                 info(1);
1471         }
1472         exit(0);
1473 #endif
1474 }
1475
1476 /*
1477   On windows, we do not use a fork, so we do not care less about
1478   waiting a child processes to die
1479  */
1480 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
1481 static RETSIGTYPE
1482 child_cleanup(int signo _U_)
1483 {
1484   wait(NULL);
1485 }
1486 #endif /* HAVE_FORK && HAVE_VFORK */
1487
1488 static void
1489 info(register int verbose)
1490 {
1491         struct pcap_stat stat;
1492
1493         /*
1494          * Older versions of libpcap didn't set ps_ifdrop on some
1495          * platforms; initialize it to 0 to handle that.
1496          */
1497         stat.ps_ifdrop = 0;
1498         if (pcap_stats(pd, &stat) < 0) {
1499                 (void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd));
1500                 infoprint = 0;
1501                 return;
1502         }
1503
1504         if (!verbose)
1505                 fprintf(stderr, "%s: ", program_name);
1506
1507         (void)fprintf(stderr, "%u packet%s captured", packets_captured,
1508             PLURAL_SUFFIX(packets_captured));
1509         if (!verbose)
1510                 fputs(", ", stderr);
1511         else
1512                 putc('\n', stderr);
1513         (void)fprintf(stderr, "%u packet%s received by filter", stat.ps_recv,
1514             PLURAL_SUFFIX(stat.ps_recv));
1515         if (!verbose)
1516                 fputs(", ", stderr);
1517         else
1518                 putc('\n', stderr);
1519         (void)fprintf(stderr, "%u packet%s dropped by kernel", stat.ps_drop,
1520             PLURAL_SUFFIX(stat.ps_drop));
1521         if (stat.ps_ifdrop != 0) {
1522                 if (!verbose)
1523                         fputs(", ", stderr);
1524                 else
1525                         putc('\n', stderr);
1526                 (void)fprintf(stderr, "%u packet%s dropped by interface\n",
1527                     stat.ps_ifdrop, PLURAL_SUFFIX(stat.ps_ifdrop));
1528         } else
1529                 putc('\n', stderr);
1530         infoprint = 0;
1531 }
1532
1533 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
1534 static void
1535 compress_savefile(const char *filename)
1536 {
1537 # ifdef HAVE_FORK
1538         if (fork())
1539 # else
1540         if (vfork())
1541 # endif
1542                 return;
1543         /*
1544          * Set to lowest priority so that this doesn't disturb the capture
1545          */
1546 #ifdef NZERO
1547         setpriority(PRIO_PROCESS, 0, NZERO - 1);
1548 #else
1549         setpriority(PRIO_PROCESS, 0, 19);
1550 #endif
1551         if (execlp(zflag, zflag, filename, (char *)NULL) == -1)
1552                 fprintf(stderr,
1553                         "compress_savefile:execlp(%s, %s): %s\n",
1554                         zflag,
1555                         filename,
1556                         strerror(errno));
1557 # ifdef HAVE_FORK
1558         exit(1);
1559 # else
1560         _exit(1);
1561 # endif
1562 }
1563 #else  /* HAVE_FORK && HAVE_VFORK */
1564 static void
1565 compress_savefile(const char *filename)
1566 {
1567         fprintf(stderr,
1568                 "compress_savefile failed. Functionality not implemented under your system\n");
1569 }
1570 #endif /* HAVE_FORK && HAVE_VFORK */
1571
1572 static void
1573 dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1574 {
1575         struct dump_info *dump_info;
1576
1577         ++packets_captured;
1578
1579         ++infodelay;
1580
1581         dump_info = (struct dump_info *)user;
1582
1583         /*
1584          * XXX - this won't force the file to rotate on the specified time
1585          * boundary, but it will rotate on the first packet received after the
1586          * specified Gflag number of seconds. Note: if a Gflag time boundary
1587          * and a Cflag size boundary coincide, the time rotation will occur
1588          * first thereby cancelling the Cflag boundary (since the file should
1589          * be 0).
1590          */
1591         if (Gflag != 0) {
1592                 /* Check if it is time to rotate */
1593                 time_t t;
1594
1595                 /* Get the current time */
1596                 if ((t = time(NULL)) == (time_t)-1) {
1597                         error("dump_and_trunc_packet: can't get current_time: %s",
1598                             pcap_strerror(errno));
1599                 }
1600
1601
1602                 /* If the time is greater than the specified window, rotate */
1603                 if (t - Gflag_time >= Gflag) {
1604                         /* Update the Gflag_time */
1605                         Gflag_time = t;
1606                         /* Update Gflag_count */
1607                         Gflag_count++;
1608                         /*
1609                          * Close the current file and open a new one.
1610                          */
1611                         pcap_dump_close(dump_info->p);
1612
1613                         /*
1614                          * Compress the file we just closed, if the user asked for it
1615                          */
1616                         if (zflag != NULL)
1617                                 compress_savefile(dump_info->CurrentFileName);
1618
1619                         /*
1620                          * Check to see if we've exceeded the Wflag (when
1621                          * not using Cflag).
1622                          */
1623                         if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) {
1624                                 (void)fprintf(stderr, "Maximum file limit reached: %d\n",
1625                                     Wflag);
1626                                 exit(0);
1627                                 /* NOTREACHED */
1628                         }
1629                         if (dump_info->CurrentFileName != NULL)
1630                                 free(dump_info->CurrentFileName);
1631                         /* Allocate space for max filename + \0. */
1632                         dump_info->CurrentFileName = (char *)malloc(NAME_MAX + 1);
1633                         if (dump_info->CurrentFileName == NULL)
1634                                 error("dump_packet_and_trunc: malloc");
1635                         /*
1636                          * This is always the first file in the Cflag
1637                          * rotation: e.g. 0
1638                          * We also don't need numbering if Cflag is not set.
1639                          */
1640                         if (Cflag != 0)
1641                                 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0,
1642                                     WflagChars);
1643                         else
1644                                 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0, 0);
1645
1646                         dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
1647                         if (dump_info->p == NULL)
1648                                 error("%s", pcap_geterr(pd));
1649                 }
1650         }
1651
1652         /*
1653          * XXX - this won't prevent capture files from getting
1654          * larger than Cflag - the last packet written to the
1655          * file could put it over Cflag.
1656          */
1657         if (Cflag != 0 && pcap_dump_ftell(dump_info->p) > Cflag) {
1658                 /*
1659                  * Close the current file and open a new one.
1660                  */
1661                 pcap_dump_close(dump_info->p);
1662
1663                 /*
1664                  * Compress the file we just closed, if the user asked for it
1665                  */
1666                 if (zflag != NULL)
1667                         compress_savefile(dump_info->CurrentFileName);
1668
1669                 Cflag_count++;
1670                 if (Wflag > 0) {
1671                         if (Cflag_count >= Wflag)
1672                                 Cflag_count = 0;
1673                 }
1674                 if (dump_info->CurrentFileName != NULL)
1675                         free(dump_info->CurrentFileName);
1676                 dump_info->CurrentFileName = (char *)malloc(NAME_MAX + 1);
1677                 if (dump_info->CurrentFileName == NULL)
1678                         error("dump_packet_and_trunc: malloc");
1679                 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, Cflag_count, WflagChars);
1680                 dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
1681                 if (dump_info->p == NULL)
1682                         error("%s", pcap_geterr(pd));
1683         }
1684
1685         pcap_dump((u_char *)dump_info->p, h, sp);
1686 #ifdef HAVE_PCAP_DUMP_FLUSH
1687         if (Uflag)
1688                 pcap_dump_flush(dump_info->p);
1689 #endif
1690
1691         --infodelay;
1692         if (infoprint)
1693                 info(0);
1694 }
1695
1696 static void
1697 dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1698 {
1699         ++packets_captured;
1700
1701         ++infodelay;
1702
1703         pcap_dump(user, h, sp);
1704 #ifdef HAVE_PCAP_DUMP_FLUSH
1705         if (Uflag)
1706                 pcap_dump_flush((pcap_dumper_t *)user);
1707 #endif
1708
1709         --infodelay;
1710         if (infoprint)
1711                 info(0);
1712 }
1713
1714 static void
1715 print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1716 {
1717         struct print_info *print_info;
1718         u_int hdrlen;
1719
1720         ++packets_captured;
1721
1722         ++infodelay;
1723         ts_print(&h->ts);
1724
1725         print_info = (struct print_info *)user;
1726
1727         /*
1728          * Some printers want to check that they're not walking off the
1729          * end of the packet.
1730          * Rather than pass it all the way down, we set this global.
1731          */
1732         snapend = sp + h->caplen;
1733
1734         if(print_info->ndo_type) {
1735                 hdrlen = (*print_info->p.ndo_printer)(print_info->ndo, h, sp);
1736         } else {
1737                 hdrlen = (*print_info->p.printer)(h, sp);
1738         }
1739
1740         if (Xflag) {
1741                 /*
1742                  * Print the raw packet data in hex and ASCII.
1743                  */
1744                 if (Xflag > 1) {
1745                         /*
1746                          * Include the link-layer header.
1747                          */
1748                         hex_and_ascii_print("\n\t", sp, h->caplen);
1749                 } else {
1750                         /*
1751                          * Don't include the link-layer header - and if
1752                          * we have nothing past the link-layer header,
1753                          * print nothing.
1754                          */
1755                         if (h->caplen > hdrlen)
1756                                 hex_and_ascii_print("\n\t", sp + hdrlen,
1757                                     h->caplen - hdrlen);
1758                 }
1759         } else if (xflag) {
1760                 /*
1761                  * Print the raw packet data in hex.
1762                  */
1763                 if (xflag > 1) {
1764                         /*
1765                          * Include the link-layer header.
1766                          */
1767                         hex_print("\n\t", sp, h->caplen);
1768                 } else {
1769                         /*
1770                          * Don't include the link-layer header - and if
1771                          * we have nothing past the link-layer header,
1772                          * print nothing.
1773                          */
1774                         if (h->caplen > hdrlen)
1775                                 hex_print("\n\t", sp + hdrlen,
1776                                     h->caplen - hdrlen);
1777                 }
1778         } else if (Aflag) {
1779                 /*
1780                  * Print the raw packet data in ASCII.
1781                  */
1782                 if (Aflag > 1) {
1783                         /*
1784                          * Include the link-layer header.
1785                          */
1786                         ascii_print(sp, h->caplen);
1787                 } else {
1788                         /*
1789                          * Don't include the link-layer header - and if
1790                          * we have nothing past the link-layer header,
1791                          * print nothing.
1792                          */
1793                         if (h->caplen > hdrlen)
1794                                 ascii_print(sp + hdrlen, h->caplen - hdrlen);
1795                 }
1796         }
1797
1798         putchar('\n');
1799
1800         --infodelay;
1801         if (infoprint)
1802                 info(0);
1803 }
1804
1805 #ifdef WIN32
1806         /*
1807          * XXX - there should really be libpcap calls to get the version
1808          * number as a string (the string would be generated from #defines
1809          * at run time, so that it's not generated from string constants
1810          * in the library, as, on many UNIX systems, those constants would
1811          * be statically linked into the application executable image, and
1812          * would thus reflect the version of libpcap on the system on
1813          * which the application was *linked*, not the system on which it's
1814          * *running*.
1815          *
1816          * That routine should be documented, unlike the "version[]"
1817          * string, so that UNIX vendors providing their own libpcaps
1818          * don't omit it (as a couple of vendors have...).
1819          *
1820          * Packet.dll should perhaps also export a routine to return the
1821          * version number of the Packet.dll code, to supply the
1822          * "Wpcap_version" information on Windows.
1823          */
1824         char WDversion[]="current-cvs.tcpdump.org";
1825 #if !defined(HAVE_GENERATED_VERSION)
1826         char version[]="current-cvs.tcpdump.org";
1827 #endif
1828         char pcap_version[]="current-cvs.tcpdump.org";
1829         char Wpcap_version[]="3.1";
1830 #endif
1831
1832 /*
1833  * By default, print the specified data out in hex and ASCII.
1834  */
1835 static void
1836 ndo_default_print(netdissect_options *ndo _U_, const u_char *bp, u_int length)
1837 {
1838         hex_and_ascii_print("\n\t", bp, length); /* pass on lf and identation string */
1839 }
1840
1841 void
1842 default_print(const u_char *bp, u_int length)
1843 {
1844         ndo_default_print(gndo, bp, length);
1845 }
1846
1847 #ifdef SIGINFO
1848 RETSIGTYPE requestinfo(int signo _U_)
1849 {
1850         if (infodelay)
1851                 ++infoprint;
1852         else
1853                 info(0);
1854 }
1855 #endif
1856
1857 /*
1858  * Called once each second in verbose mode while dumping to file
1859  */
1860 #ifdef USE_WIN32_MM_TIMER
1861 void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_,
1862                                   DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_)
1863 {
1864         struct pcap_stat stat;
1865
1866         if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
1867                 fprintf(stderr, "Got %u\r", packets_captured);
1868 }
1869 #elif defined(HAVE_ALARM)
1870 static void verbose_stats_dump(int sig _U_)
1871 {
1872         struct pcap_stat stat;
1873
1874         if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
1875                 fprintf(stderr, "Got %u\r", packets_captured);
1876         alarm(1);
1877 }
1878 #endif
1879
1880 static void
1881 usage(void)
1882 {
1883         extern char version[];
1884 #ifndef HAVE_PCAP_LIB_VERSION
1885 #if defined(WIN32) || defined(HAVE_PCAP_VERSION)
1886         extern char pcap_version[];
1887 #else /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
1888         static char pcap_version[] = "unknown";
1889 #endif /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
1890 #endif /* HAVE_PCAP_LIB_VERSION */
1891
1892 #ifdef HAVE_PCAP_LIB_VERSION
1893 #ifdef WIN32
1894         (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
1895 #else /* WIN32 */
1896         (void)fprintf(stderr, "%s version %s\n", program_name, version);
1897 #endif /* WIN32 */
1898         (void)fprintf(stderr, "%s\n",pcap_lib_version());
1899 #else /* HAVE_PCAP_LIB_VERSION */
1900 #ifdef WIN32
1901         (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
1902         (void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version);
1903 #else /* WIN32 */
1904         (void)fprintf(stderr, "%s version %s\n", program_name, version);
1905         (void)fprintf(stderr, "libpcap version %s\n", pcap_version);
1906 #endif /* WIN32 */
1907 #endif /* HAVE_PCAP_LIB_VERSION */
1908         (void)fprintf(stderr,
1909 "Usage: %s [-aAbd" D_FLAG "efhH" I_FLAG J_FLAG "KlLnNOpqRStu" U_FLAG "vxX]" B_FLAG_USAGE " [ -c count ]\n", program_name);
1910         (void)fprintf(stderr,
1911 "\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n");
1912         (void)fprintf(stderr,
1913 "\t\t[ -i interface ]" j_FLAG_USAGE " [ -M secret ]\n");
1914         (void)fprintf(stderr,
1915 "\t\t[ -r file ] [ -s snaplen ] [ -T type ] [ -w file ]\n");
1916         (void)fprintf(stderr,
1917 "\t\t[ -W filecount ] [ -y datalinktype ] [ -z command ]\n");
1918         (void)fprintf(stderr,
1919 "\t\t[ -Z user ] [ expression ]\n");
1920         exit(1);
1921 }
1922
1923
1924
1925 /* VARARGS */
1926 static void
1927 ndo_error(netdissect_options *ndo _U_, const char *fmt, ...)
1928 {
1929         va_list ap;
1930
1931         (void)fprintf(stderr, "%s: ", program_name);
1932         va_start(ap, fmt);
1933         (void)vfprintf(stderr, fmt, ap);
1934         va_end(ap);
1935         if (*fmt) {
1936                 fmt += strlen(fmt);
1937                 if (fmt[-1] != '\n')
1938                         (void)fputc('\n', stderr);
1939         }
1940         exit(1);
1941         /* NOTREACHED */
1942 }
1943
1944 /* VARARGS */
1945 static void
1946 ndo_warning(netdissect_options *ndo _U_, const char *fmt, ...)
1947 {
1948         va_list ap;
1949
1950         (void)fprintf(stderr, "%s: WARNING: ", program_name);
1951         va_start(ap, fmt);
1952         (void)vfprintf(stderr, fmt, ap);
1953         va_end(ap);
1954         if (*fmt) {
1955                 fmt += strlen(fmt);
1956                 if (fmt[-1] != '\n')
1957                         (void)fputc('\n', stderr);
1958         }
1959 }