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 1.271.2.11 2008-09-25 21:50:04 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 int dflag;                      /* print filter code */
  94 int Lflag;                      /* list available data link types and exit */
  95 char *zflag = NULL;             /* compress each savefile using a specified command (like gzip or bzip2) */
  96
  97 static int infodelay;
  98 static int infoprint;
  99
 100 char *program_name;
 101
 102 int32_t thiszone;               /* seconds offset from gmt to local time */
 103
 104 /* Forwards */
 105 static RETSIGTYPE cleanup(int);
 106 static RETSIGTYPE child_cleanup(int);
 107 static void usage(void) __attribute__((noreturn));
 108 static void show_dlts_and_exit(pcap_t *pd) __attribute__((noreturn));
 109
 110 static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
 111 static void ndo_default_print(netdissect_options *, const u_char *, u_int);
 112 static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *);
 113 static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
 114 static void droproot(const char *, const char *);
 115 static void ndo_error(netdissect_options *ndo, const char *fmt, ...);
 116 static void ndo_warning(netdissect_options *ndo, const char *fmt, ...);
 117
 118 #ifdef SIGINFO
 119 RETSIGTYPE requestinfo(int);
 120 #endif
 121
 122 #if defined(USE_WIN32_MM_TIMER)
 123   #include <MMsystem.h>
 124   static UINT timer_id;
 125   static void CALLBACK verbose_stats_dump(UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR);
 126 #elif defined(HAVE_ALARM)
 127   static void verbose_stats_dump(int sig);
 128 #endif
 129
 130 static void info(int);
 131 static u_int packets_captured;
 132
 133 typedef u_int (*if_printer)(const struct pcap_pkthdr *, const u_char *);
 134
 135 struct printer {
 136         if_printer f;
 137         int type;
 138 };
 139
 140 static struct printer printers[] = {
 141         { arcnet_if_print,      DLT_ARCNET },
 142 #ifdef DLT_ARCNET_LINUX
 143         { arcnet_linux_if_print, DLT_ARCNET_LINUX },
 144 #endif
 145         { ether_if_print,       DLT_EN10MB },
 146         { token_if_print,       DLT_IEEE802 },
 147 #ifdef DLT_LANE8023
 148         { lane_if_print,        DLT_LANE8023 },
 149 #endif
 150 #ifdef DLT_CIP
 151         { cip_if_print,         DLT_CIP },
 152 #endif
 153 #ifdef DLT_ATM_CLIP
 154         { cip_if_print,         DLT_ATM_CLIP },
 155 #endif
 156         { sl_if_print,          DLT_SLIP },
 157 #ifdef DLT_SLIP_BSDOS
 158         { sl_bsdos_if_print,    DLT_SLIP_BSDOS },
 159 #endif
 160         { ppp_if_print,         DLT_PPP },
 161 #ifdef DLT_PPP_WITHDIRECTION
 162         { ppp_if_print,         DLT_PPP_WITHDIRECTION },
 163 #endif
 164 #ifdef DLT_PPP_BSDOS
 165         { ppp_bsdos_if_print,   DLT_PPP_BSDOS },
 166 #endif
 167         { fddi_if_print,        DLT_FDDI },
 168         { null_if_print,        DLT_NULL },
 169 #ifdef DLT_LOOP
 170         { null_if_print,        DLT_LOOP },
 171 #endif
 172         { raw_if_print,         DLT_RAW },
 173         { atm_if_print,         DLT_ATM_RFC1483 },
 174 #ifdef DLT_C_HDLC
 175         { chdlc_if_print,       DLT_C_HDLC },
 176 #endif
 177 #ifdef DLT_HDLC
 178         { chdlc_if_print,       DLT_HDLC },
 179 #endif
 180 #ifdef DLT_PPP_SERIAL
 181         { ppp_hdlc_if_print,    DLT_PPP_SERIAL },
 182 #endif
 183 #ifdef DLT_PPP_ETHER
 184         { pppoe_if_print,       DLT_PPP_ETHER },
 185 #endif
 186 #ifdef DLT_LINUX_SLL
 187         { sll_if_print,         DLT_LINUX_SLL },
 188 #endif
 189 #ifdef DLT_IEEE802_11
 190         { ieee802_11_if_print,  DLT_IEEE802_11},
 191 #endif
 192 #ifdef DLT_LTALK
 193         { ltalk_if_print,       DLT_LTALK },
 194 #endif
 195 #if defined(DLT_PFLOG) && defined(HAVE_NET_PFVAR_H)
 196         { pflog_if_print,       DLT_PFLOG },
 197 #endif
 198 #ifdef DLT_FR
 199         { fr_if_print,          DLT_FR },
 200 #endif
 201 #ifdef DLT_FRELAY
 202         { fr_if_print,          DLT_FRELAY },
 203 #endif
 204 #ifdef DLT_SUNATM
 205         { sunatm_if_print,      DLT_SUNATM },
 206 #endif
 207 #ifdef DLT_IP_OVER_FC
 208         { ipfc_if_print,        DLT_IP_OVER_FC },
 209 #endif
 210 #ifdef DLT_PRISM_HEADER
 211         { prism_if_print,       DLT_PRISM_HEADER },
 212 #endif
 213 #ifdef DLT_IEEE802_11_RADIO
 214         { ieee802_11_radio_if_print,    DLT_IEEE802_11_RADIO },
 215 #endif
 216 #ifdef DLT_ENC
 217         { enc_if_print,         DLT_ENC },
 218 #endif
 219 #ifdef DLT_SYMANTEC_FIREWALL
 220         { symantec_if_print,    DLT_SYMANTEC_FIREWALL },
 221 #endif
 222 #ifdef DLT_APPLE_IP_OVER_IEEE1394
 223         { ap1394_if_print,      DLT_APPLE_IP_OVER_IEEE1394 },
 224 #endif
 225 #ifdef DLT_IEEE802_11_RADIO_AVS
 226         { ieee802_11_radio_avs_if_print,        DLT_IEEE802_11_RADIO_AVS },
 227 #endif
 228 #ifdef DLT_JUNIPER_ATM1
 229         { juniper_atm1_print,   DLT_JUNIPER_ATM1 },
 230 #endif
 231 #ifdef DLT_JUNIPER_ATM2
 232         { juniper_atm2_print,   DLT_JUNIPER_ATM2 },
 233 #endif
 234 #ifdef DLT_JUNIPER_MFR
 235         { juniper_mfr_print,    DLT_JUNIPER_MFR },
 236 #endif
 237 #ifdef DLT_JUNIPER_MLFR
 238         { juniper_mlfr_print,   DLT_JUNIPER_MLFR },
 239 #endif
 240 #ifdef DLT_JUNIPER_MLPPP
 241         { juniper_mlppp_print,  DLT_JUNIPER_MLPPP },
 242 #endif
 243 #ifdef DLT_JUNIPER_PPPOE
 244         { juniper_pppoe_print,  DLT_JUNIPER_PPPOE },
 245 #endif
 246 #ifdef DLT_JUNIPER_PPPOE_ATM
 247         { juniper_pppoe_atm_print, DLT_JUNIPER_PPPOE_ATM },
 248 #endif
 249 #ifdef DLT_JUNIPER_GGSN
 250         { juniper_ggsn_print,   DLT_JUNIPER_GGSN },
 251 #endif
 252 #ifdef DLT_JUNIPER_ES
 253         { juniper_es_print,     DLT_JUNIPER_ES },
 254 #endif
 255 #ifdef DLT_JUNIPER_MONITOR
 256         { juniper_monitor_print, DLT_JUNIPER_MONITOR },
 257 #endif
 258 #ifdef DLT_JUNIPER_SERVICES
 259         { juniper_services_print, DLT_JUNIPER_SERVICES },
 260 #endif
 261 #ifdef DLT_JUNIPER_ETHER
 262         { juniper_ether_print, DLT_JUNIPER_ETHER },
 263 #endif
 264 #ifdef DLT_JUNIPER_PPP
 265         { juniper_ppp_print, DLT_JUNIPER_PPP },
 266 #endif
 267 #ifdef DLT_JUNIPER_FRELAY
 268         { juniper_frelay_print, DLT_JUNIPER_FRELAY },
 269 #endif
 270 #ifdef DLT_JUNIPER_CHDLC
 271         { juniper_chdlc_print, DLT_JUNIPER_CHDLC },
 272 #endif
 273 #ifdef DLT_MFR
 274         { mfr_if_print, DLT_MFR },
 275 #endif
 276 #if defined(DLT_BLUETOOTH_HCI_H4_WITH_PHDR) && defined(HAVE_PCAP_BLUETOOTH_H)
 277         { bt_if_print, DLT_BLUETOOTH_HCI_H4_WITH_PHDR},
 278 #endif
 279         { NULL,                 0 },
 280 };
 281
 282 static if_printer
 283 lookup_printer(int type)
 284 {
 285         struct printer *p;
 286
 287         for (p = printers; p->f; ++p)
 288                 if (type == p->type)
 289                         return p->f;
 290
 291         return NULL;
 292         /* NOTREACHED */
 293 }
 294
 295 static pcap_t *pd;
 296
 297 extern int optind;
 298 extern int opterr;
 299 extern char *optarg;
 300
 301 struct print_info {
 302         if_printer printer;
 303 };
 304
 305 struct dump_info {
 306         char    *WFileName;
 307         char    *CurrentFileName;
 308         pcap_t  *pd;
 309         pcap_dumper_t *p;
 310 };
 311
 312 static void
 313 show_dlts_and_exit(pcap_t *pd)
 314 {
 315         int n_dlts;
 316         int *dlts = 0;
 317         const char *dlt_name;
 318
 319         n_dlts = pcap_list_datalinks(pd, &dlts);
 320         if (n_dlts < 0)
 321                 error("%s", pcap_geterr(pd));
 322         else if (n_dlts == 0 || !dlts)
 323                 error("No data link types.");
 324
 325         (void) fprintf(stderr, "Data link types (use option -y to set):\n");
 326
 327         while (--n_dlts >= 0) {
 328                 dlt_name = pcap_datalink_val_to_name(dlts[n_dlts]);
 329                 if (dlt_name != NULL) {
 330                         (void) fprintf(stderr, "  %s (%s)", dlt_name,
 331                             pcap_datalink_val_to_description(dlts[n_dlts]));
 332
 333                         /*
 334                          * OK, does tcpdump handle that type?
 335                          */
 336                         if (lookup_printer(dlts[n_dlts]) == NULL)
 337                                 (void) fprintf(stderr, " (printing not supported)");
 338                         putchar('\n');
 339                 } else {
 340                         (void) fprintf(stderr, "  DLT %d (printing not supported)\n",
 341                             dlts[n_dlts]);
 342                 }
 343         }
 344         free(dlts);
 345         exit(0);
 346 }
 347
 348 /*
 349  * Set up flags that might or might not be supported depending on the
 350  * version of libpcap we're using.
 351  */
 352 #if defined(HAVE_PCAP_CREATE) || defined(WIN32)
 353 #define B_FLAG          "B:"
 354 #define B_FLAG_USAGE    " [ -B size ]"
 355 #else /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
 356 #define B_FLAG
 357 #define B_FLAG_USAGE
 358 #endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
 359
 360 #ifdef HAVE_PCAP_CREATE
 361 #define I_FLAG          "I"
 362 #else /* HAVE_PCAP_CREATE */
 363 #define I_FLAG
 364 #endif /* HAVE_PCAP_CREATE */
 365
 366 #ifdef HAVE_PCAP_FINDALLDEVS
 367 #ifndef HAVE_PCAP_IF_T
 368 #undef HAVE_PCAP_FINDALLDEVS
 369 #endif
 370 #endif
 371
 372 #ifdef HAVE_PCAP_FINDALLDEVS
 373 #define D_FLAG  "D"
 374 #else
 375 #define D_FLAG
 376 #endif
 377
 378 #ifdef HAVE_PCAP_DUMP_FLUSH
 379 #define U_FLAG  "U"
 380 #else
 381 #define U_FLAG
 382 #endif
 383
 384 #ifndef WIN32
 385 /* Drop root privileges and chroot if necessary */
 386 static void
 387 droproot(const char *username, const char *chroot_dir)
 388 {
 389         struct passwd *pw = NULL;
 390
 391         if (chroot_dir && !username) {
 392                 fprintf(stderr, "tcpdump: Chroot without dropping root is insecure\n");
 393                 exit(1);
 394         }
 395
 396         pw = getpwnam(username);
 397         if (pw) {
 398                 if (chroot_dir) {
 399                         if (chroot(chroot_dir) != 0 || chdir ("/") != 0) {
 400                                 fprintf(stderr, "tcpdump: Couldn't chroot/chdir to '%.64s': %s\n",
 401                                     chroot_dir, pcap_strerror(errno));
 402                                 exit(1);
 403                         }
 404                 }
 405                 if (initgroups(pw->pw_name, pw->pw_gid) != 0 ||
 406                     setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) {
 407                         fprintf(stderr, "tcpdump: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n",
 408                             username,
 409                             (unsigned long)pw->pw_uid,
 410                             (unsigned long)pw->pw_gid,
 411                             pcap_strerror(errno));
 412                         exit(1);
 413                 }
 414         }
 415         else {
 416                 fprintf(stderr, "tcpdump: Couldn't find user '%.32s'\n",
 417                     username);
 418                 exit(1);
 419         }
 420 }
 421 #endif /* WIN32 */
 422
 423 static int
 424 getWflagChars(int x)
 425 {
 426         int c = 0;
 427
 428         x -= 1;
 429         while (x > 0) {
 430                 c += 1;
 431                 x /= 10;
 432         }
 433
 434         return c;
 435 }
 436
 437
 438 static void
 439 MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars)
 440 {
 441         char *filename = malloc(NAME_MAX + 1);
 442
 443         /* Process with strftime if Gflag is set. */
 444         if (Gflag != 0) {
 445           struct tm *local_tm;
 446
 447           /* Convert Gflag_time to a usable format */
 448           if ((local_tm = localtime(&Gflag_time)) == NULL) {
 449                   error("MakeTimedFilename: localtime");
 450           }
 451
 452           /* There's no good way to detect an error in strftime since a return
 453            * value of 0 isn't necessarily failure.
 454            */
 455           strftime(filename, NAME_MAX, orig_name, local_tm);
 456         } else {
 457           strncpy(filename, orig_name, NAME_MAX);
 458         }
 459
 460         if (cnt == 0 && max_chars == 0)
 461                 strncpy(buffer, filename, NAME_MAX + 1);
 462         else
 463                 if (snprintf(buffer, NAME_MAX + 1, "%s%0*d", filename, max_chars, cnt) > NAME_MAX)
 464                   /* Report an error if the filename is too large */
 465                   error("too many output files or filename is too long (> %d)", NAME_MAX);
 466         free(filename);
 467 }
 468
 469 static int tcpdump_printf(netdissect_options *ndo _U_,
 470                           const char *fmt, ...)
 471 {
 472
 473   va_list args;
 474   int ret;
 475
 476   va_start(args, fmt);
 477   ret=vfprintf(stdout, fmt, args);
 478   va_end(args);
 479
 480   return ret;
 481 }
 482
 483 int
 484 main(int argc, char **argv)
 485 {
 486         register int cnt, op, i;
 487         bpf_u_int32 localnet, netmask;
 488         register char *cp, *infile, *cmdbuf, *device, *RFileName, *WFileName;
 489         pcap_handler callback;
 490         int type;
 491         struct bpf_program fcode;
 492 #ifndef WIN32
 493         RETSIGTYPE (*oldhandler)(int);
 494 #endif
 495         struct print_info printinfo;
 496         struct dump_info dumpinfo;
 497         u_char *pcap_userdata;
 498         char ebuf[PCAP_ERRBUF_SIZE];
 499         char *username = NULL;
 500         char *chroot_dir = NULL;
 501 #ifdef HAVE_PCAP_FINDALLDEVS
 502         pcap_if_t *devpointer;
 503         int devnum;
 504 #endif
 505         int status;
 506 #ifdef WIN32
 507         if(wsockinit() != 0) return 1;
 508 #endif /* WIN32 */
 509
 510         gndo->ndo_Oflag=1;
 511         gndo->ndo_Rflag=1;
 512         gndo->ndo_dlt=-1;
 513         gndo->ndo_default_print=ndo_default_print;
 514         gndo->ndo_printf=tcpdump_printf;
 515         gndo->ndo_error=ndo_error;
 516         gndo->ndo_warning=ndo_warning;
 517         gndo->ndo_snaplen = DEFAULT_SNAPLEN;
 518
 519         cnt = -1;
 520         device = NULL;
 521         infile = NULL;
 522         RFileName = NULL;
 523         WFileName = NULL;
 524         if ((cp = strrchr(argv[0], '/')) != NULL)
 525                 program_name = cp + 1;
 526         else
 527                 program_name = argv[0];
 528
 529         if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
 530                 error("%s", ebuf);
 531
 532 #ifdef LIBSMI
 533         smiInit("tcpdump");
 534 #endif
 535
 536         opterr = 0;
 537         while (
 538             (op = getopt(argc, argv, "aA" B_FLAG "c:C:d" D_FLAG "eE:fF:G:i:" I_FLAG "KlLm:M:nNOpqr:Rs:StT:u" U_FLAG "vw:W:xXy:Yz:Z:")) != -1)
 539                 switch (op) {
 540
 541                 case 'a':
 542                         /* compatibility for old -a */
 543                         break;
 544
 545                 case 'A':
 546                         ++Aflag;
 547                         break;
 548
 549 #if defined(HAVE_PCAP_CREATE) || defined(WIN32)
 550                 case 'B':
 551                         Bflag = atoi(optarg)*1024;
 552                         if (Bflag <= 0)
 553                                 error("invalid packet buffer size %s", optarg);
 554                         break;
 555 #endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
 556
 557                 case 'c':
 558                         cnt = atoi(optarg);
 559                         if (cnt <= 0)
 560                                 error("invalid packet count %s", optarg);
 561                         break;
 562
 563                 case 'C':
 564                         Cflag = atoi(optarg) * 1000000;
 565                         if (Cflag < 0)
 566                                 error("invalid file size %s", optarg);
 567                         break;
 568
 569                 case 'd':
 570                         ++dflag;
 571                         break;
 572
 573 #ifdef HAVE_PCAP_FINDALLDEVS
 574                 case 'D':
 575                         if (pcap_findalldevs(&devpointer, ebuf) < 0)
 576                                 error("%s", ebuf);
 577                         else {
 578                                 for (i = 0; devpointer != 0; i++) {
 579                                         printf("%d.%s", i+1, devpointer->name);
 580                                         if (devpointer->description != NULL)
 581                                                 printf(" (%s)", devpointer->description);
 582                                         printf("\n");
 583                                         devpointer = devpointer->next;
 584                                 }
 585                         }
 586                         return 0;
 587 #endif /* HAVE_PCAP_FINDALLDEVS */
 588
 589                 case 'L':
 590                         Lflag++;
 591                         break;
 592
 593                 case 'e':
 594                         ++eflag;
 595                         break;
 596
 597                 case 'E':
 598 #ifndef HAVE_LIBCRYPTO
 599                         warning("crypto code not compiled in");
 600 #endif
 601                         gndo->ndo_espsecret = optarg;
 602                         break;
 603
 604                 case 'f':
 605                         ++fflag;
 606                         break;
 607
 608                 case 'F':
 609                         infile = optarg;
 610                         break;
 611
 612                 case 'G':
 613                         Gflag = atoi(optarg);
 614                         if (Gflag < 0)
 615                                 error("invalid number of seconds %s", optarg);
 616
 617                         /* We will create one file initially. */
 618                         Gflag_count = 0;
 619
 620                         /* Grab the current time for rotation use. */
 621                         if ((Gflag_time = time(NULL)) == (time_t)-1) {
 622                                 error("main: can't get current time: %s",
 623                                     pcap_strerror(errno));
 624                         }
 625                         break;
 626
 627                 case 'i':
 628                         if (optarg[0] == '0' && optarg[1] == 0)
 629                                 error("Invalid adapter index");
 630
 631 #ifdef HAVE_PCAP_FINDALLDEVS
 632                         /*
 633                          * If the argument is a number, treat it as
 634                          * an index into the list of adapters, as
 635                          * printed by "tcpdump -D".
 636                          *
 637                          * This should be OK on UNIX systems, as interfaces
 638                          * shouldn't have names that begin with digits.
 639                          * It can be useful on Windows, where more than
 640                          * one interface can have the same name.
 641                          */
 642                         if ((devnum = atoi(optarg)) != 0) {
 643                                 if (devnum < 0)
 644                                         error("Invalid adapter index");
 645
 646                                 if (pcap_findalldevs(&devpointer, ebuf) < 0)
 647                                         error("%s", ebuf);
 648                                 else {
 649                                         for (i = 0; i < devnum-1; i++){
 650                                                 devpointer = devpointer->next;
 651                                                 if (devpointer == NULL)
 652                                                         error("Invalid adapter index");
 653                                         }
 654                                 }
 655                                 device = devpointer->name;
 656                                 break;
 657                         }
 658 #endif /* HAVE_PCAP_FINDALLDEVS */
 659                         device = optarg;
 660                         break;
 661
 662 #ifdef HAVE_PCAP_CREATE
 663                 case 'I':
 664                         ++Iflag;
 665                         break;
 666 #endif /* HAVE_PCAP_CREATE */
 667
 668                 case 'l':
 669 #ifdef WIN32
 670                         /*
 671                          * _IOLBF is the same as _IOFBF in Microsoft's C
 672                          * libraries; the only alternative they offer
 673                          * is _IONBF.
 674                          *
 675                          * XXX - this should really be checking for MSVC++,
 676                          * not WIN32, if, for example, MinGW has its own
 677                          * C library that is more UNIX-compatible.
 678                          */
 679                         setvbuf(stdout, NULL, _IONBF, 0);
 680 #else /* WIN32 */
 681 #ifdef HAVE_SETLINEBUF
 682                         setlinebuf(stdout);
 683 #else
 684                         setvbuf(stdout, NULL, _IOLBF, 0);
 685 #endif
 686 #endif /* WIN32 */
 687                         break;
 688
 689                 case 'K':
 690                         ++Kflag;
 691                         break;
 692
 693                 case 'm':
 694 #ifdef LIBSMI
 695                         if (smiLoadModule(optarg) == 0) {
 696                                 error("could not load MIB module %s", optarg);
 697                         }
 698                         sflag = 1;
 699 #else
 700                         (void)fprintf(stderr, "%s: ignoring option `-m %s' ",
 701                                       program_name, optarg);
 702                         (void)fprintf(stderr, "(no libsmi support)\n");
 703 #endif
 704                         break;
 705
 706                 case 'M':
 707                         /* TCP-MD5 shared secret */
 708 #ifndef HAVE_LIBCRYPTO
 709                         warning("crypto code not compiled in");
 710 #endif
 711                         tcpmd5secret = optarg;
 712                         break;
 713
 714                 case 'n':
 715                         ++nflag;
 716                         break;
 717
 718                 case 'N':
 719                         ++Nflag;
 720                         break;
 721
 722                 case 'O':
 723                         Oflag = 0;
 724                         break;
 725
 726                 case 'p':
 727                         ++pflag;
 728                         break;
 729
 730                 case 'q':
 731                         ++qflag;
 732                         ++suppress_default_print;
 733                         break;
 734
 735                 case 'r':
 736                         RFileName = optarg;
 737                         break;
 738
 739                 case 'R':
 740                         Rflag = 0;
 741                         break;
 742
 743                 case 's': {
 744                         char *end;
 745
 746                         snaplen = strtol(optarg, &end, 0);
 747                         if (optarg == end || *end != '\0'
 748                             || snaplen < 0 || snaplen > 65535)
 749                                 error("invalid snaplen %s", optarg);
 750                         else if (snaplen == 0)
 751                                 snaplen = 65535;
 752                         break;
 753                 }
 754
 755                 case 'S':
 756                         ++Sflag;
 757                         break;
 758
 759                 case 't':
 760                         ++tflag;
 761                         break;
 762
 763                 case 'T':
 764                         if (strcasecmp(optarg, "vat") == 0)
 765                                 packettype = PT_VAT;
 766                         else if (strcasecmp(optarg, "wb") == 0)
 767                                 packettype = PT_WB;
 768                         else if (strcasecmp(optarg, "rpc") == 0)
 769                                 packettype = PT_RPC;
 770                         else if (strcasecmp(optarg, "rtp") == 0)
 771                                 packettype = PT_RTP;
 772                         else if (strcasecmp(optarg, "rtcp") == 0)
 773                                 packettype = PT_RTCP;
 774                         else if (strcasecmp(optarg, "snmp") == 0)
 775                                 packettype = PT_SNMP;
 776                         else if (strcasecmp(optarg, "cnfp") == 0)
 777                                 packettype = PT_CNFP;
 778                         else if (strcasecmp(optarg, "tftp") == 0)
 779                                 packettype = PT_TFTP;
 780                         else if (strcasecmp(optarg, "aodv") == 0)
 781                                 packettype = PT_AODV;
 782                         else
 783                                 error("unknown packet type `%s'", optarg);
 784                         break;
 785
 786                 case 'u':
 787                         ++uflag;
 788                         break;
 789
 790 #ifdef HAVE_PCAP_DUMP_FLUSH
 791                 case 'U':
 792                         ++Uflag;
 793                         break;
 794 #endif
 795
 796                 case 'v':
 797                         ++vflag;
 798                         break;
 799
 800                 case 'w':
 801                         WFileName = optarg;
 802                         break;
 803
 804                 case 'W':
 805                         Wflag = atoi(optarg);
 806                         if (Wflag < 0)
 807                                 error("invalid number of output files %s", optarg);
 808                         WflagChars = getWflagChars(Wflag);
 809                         break;
 810
 811                 case 'x':
 812                         ++xflag;
 813                         ++suppress_default_print;
 814                         break;
 815
 816                 case 'X':
 817                         ++Xflag;
 818                         ++suppress_default_print;
 819                         break;
 820
 821                 case 'y':
 822                         gndo->ndo_dltname = optarg;
 823                         gndo->ndo_dlt =
 824                           pcap_datalink_name_to_val(gndo->ndo_dltname);
 825                         if (gndo->ndo_dlt < 0)
 826                                 error("invalid data link type %s", gndo->ndo_dltname);
 827                         break;
 828
 829 #if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
 830                 case 'Y':
 831                         {
 832                         /* Undocumented flag */
 833 #ifdef HAVE_PCAP_DEBUG
 834                         extern int pcap_debug;
 835                         pcap_debug = 1;
 836 #else
 837                         extern int yydebug;
 838                         yydebug = 1;
 839 #endif
 840                         }
 841                         break;
 842 #endif
 843                 case 'z':
 844                         if (optarg) {
 845                                 zflag = strdup(optarg);
 846                         } else {
 847                                 usage();
 848                                 /* NOTREACHED */
 849                         }
 850                         break;
 851
 852                 case 'Z':
 853                         if (optarg) {
 854                                 username = strdup(optarg);
 855                         }
 856                         else {
 857                                 usage();
 858                                 /* NOTREACHED */
 859                         }
 860                         break;
 861
 862                 default:
 863                         usage();
 864                         /* NOTREACHED */
 865                 }
 866
 867         switch (tflag) {
 868
 869         case 0: /* Default */
 870         case 4: /* Default + Date*/
 871                 thiszone = gmt2local(0);
 872                 break;
 873
 874         case 1: /* No time stamp */
 875         case 2: /* Unix timeval style */
 876         case 3: /* Microseconds since previous packet */
 877         case 5: /* Microseconds since first packet */
 878                 break;
 879
 880         default: /* Not supported */
 881                 error("only -t, -tt, -ttt, -tttt and -ttttt are supported");
 882                 break;
 883         }
 884
 885 #ifdef WITH_CHROOT
 886         /* if run as root, prepare for chrooting */
 887         if (getuid() == 0 || geteuid() == 0) {
 888                 /* future extensibility for cmd-line arguments */
 889                 if (!chroot_dir)
 890                         chroot_dir = WITH_CHROOT;
 891         }
 892 #endif
 893
 894 #ifdef WITH_USER
 895         /* if run as root, prepare for dropping root privileges */
 896         if (getuid() == 0 || geteuid() == 0) {
 897                 /* Run with '-Z root' to restore old behaviour */
 898                 if (!username)
 899                         username = WITH_USER;
 900         }
 901 #endif
 902
 903         if (RFileName != NULL) {
 904                 int dlt;
 905                 const char *dlt_name;
 906
 907 #ifndef WIN32
 908                 /*
 909                  * We don't need network access, so relinquish any set-UID
 910                  * or set-GID privileges we have (if any).
 911                  *
 912                  * We do *not* want set-UID privileges when opening a
 913                  * trace file, as that might let the user read other
 914                  * people's trace files (especially if we're set-UID
 915                  * root).
 916                  */
 917                 if (setgid(getgid()) != 0 || setuid(getuid()) != 0 )
 918                         fprintf(stderr, "Warning: setgid/setuid failed !\n");
 919 #endif /* WIN32 */
 920                 pd = pcap_open_offline(RFileName, ebuf);
 921                 if (pd == NULL)
 922                         error("%s", ebuf);
 923                 dlt = pcap_datalink(pd);
 924                 dlt_name = pcap_datalink_val_to_name(dlt);
 925                 if (dlt_name == NULL) {
 926                         fprintf(stderr, "reading from file %s, link-type %u\n",
 927                             RFileName, dlt);
 928                 } else {
 929                         fprintf(stderr,
 930                             "reading from file %s, link-type %s (%s)\n",
 931                             RFileName, dlt_name,
 932                             pcap_datalink_val_to_description(dlt));
 933                 }
 934                 localnet = 0;
 935                 netmask = 0;
 936                 if (fflag != 0)
 937                         error("-f and -r options are incompatible");
 938         } else {
 939                 if (device == NULL) {
 940                         device = pcap_lookupdev(ebuf);
 941                         if (device == NULL)
 942                                 error("%s", ebuf);
 943                 }
 944 #ifdef WIN32
 945                 if(strlen(device) == 1) //we assume that an ASCII string is always longer than 1 char
 946                 {                                               //a Unicode string has a \0 as second byte (so strlen() is 1)
 947                         fprintf(stderr, "%s: listening on %ws\n", program_name, device);
 948                 }
 949                 else
 950                 {
 951                         fprintf(stderr, "%s: listening on %s\n", program_name, device);
 952                 }
 953
 954                 fflush(stderr);
 955 #endif /* WIN32 */
 956 #ifdef HAVE_PCAP_CREATE
 957                 pd = pcap_create(device, ebuf);
 958                 if (pd == NULL)
 959                         error("%s", ebuf);
 960                 status = pcap_set_snaplen(pd, snaplen);
 961                 if (status != 0)
 962                         error("%s: pcap_set_snaplen failed: %s",
 963                             device, pcap_statustostr(status));
 964                 status = pcap_set_promisc(pd, !pflag);
 965                 if (status != 0)
 966                         error("%s: pcap_set_promisc failed: %s",
 967                             device, pcap_statustostr(status));
 968                 if (Iflag) {
 969                         status = pcap_set_rfmon(pd, 1);
 970                         if (status != 0)
 971                                 error("%s: pcap_set_rfmon failed: %s",
 972                                     device, pcap_statustostr(status));
 973                 }
 974                 status = pcap_set_timeout(pd, 1000);
 975                 if (status != 0)
 976                         error("%s: pcap_set_timeout failed: %s",
 977                             device, pcap_statustostr(status));
 978                 if (Bflag != 0) {
 979                         status = pcap_set_buffer_size(pd, Bflag);
 980                         if (status != 0)
 981                                 error("%s: pcap_set_buffer_size failed: %s",
 982                                     device, pcap_statustostr(status));
 983                 }
 984                 status = pcap_activate(pd);
 985                 if (status < 0) {
 986                         /*
 987                          * pcap_activate() failed.
 988                          */
 989                         cp = pcap_geterr(pd);
 990                         if (status == PCAP_ERROR)
 991                                 error("%s", cp);
 992                         else if ((status == PCAP_ERROR_NO_SUCH_DEVICE ||
 993                                   status == PCAP_ERROR_PERM_DENIED) &&
 994                                  *cp != '\0')
 995                                 error("%s: %s\n(%s)", device,
 996                                     pcap_statustostr(status), cp);
 997                         else
 998                                 error("%s: %s", device,
 999                                     pcap_statustostr(status));
1000                 } else if (status > 0) {
1001                         /*
1002                          * pcap_activate() succeeded, but it's warning us
1003                          * of a problem it had.
1004                          */
1005                         cp = pcap_geterr(pd);
1006                         if (status == PCAP_WARNING)
1007                                 warning("%s", cp);
1008                         else if (status == PCAP_WARNING_PROMISC_NOTSUP &&
1009                                  *cp != '\0')
1010                                 warning("%s: %s\n(%s)", device,
1011                                     pcap_statustostr(status), cp);
1012                         else
1013                                 warning("%s: %s", device,
1014                                     pcap_statustostr(status));
1015                 }
1016 #else
1017                 *ebuf = '\0';
1018                 pd = pcap_open_live(device, snaplen, !pflag, 1000, ebuf);
1019                 if (pd == NULL)
1020                         error("%s", ebuf);
1021                 else if (*ebuf)
1022                         warning("%s", ebuf);
1023 #endif /* HAVE_PCAP_CREATE */
1024                 /*
1025                  * Let user own process after socket has been opened.
1026                  */
1027 #ifndef WIN32
1028                 if (setgid(getgid()) != 0 || setuid(getuid()) != 0)
1029                         fprintf(stderr, "Warning: setgid/setuid failed !\n");
1030 #endif /* WIN32 */
1031 #if !defined(HAVE_PCAP_CREATE) && defined(WIN32)
1032                 if(Bflag != 0)
1033                         if(pcap_setbuff(pd, Bflag)==-1){
1034                                 error("%s", pcap_geterr(pd));
1035                         }
1036 #endif /* !defined(HAVE_PCAP_CREATE) && defined(WIN32) */
1037                 if (Lflag)
1038                         show_dlts_and_exit(pd);
1039                 if (gndo->ndo_dlt >= 0) {
1040 #ifdef HAVE_PCAP_SET_DATALINK
1041                         if (pcap_set_datalink(pd, gndo->ndo_dlt) < 0)
1042                                 error("%s", pcap_geterr(pd));
1043 #else
1044                         /*
1045                          * We don't actually support changing the
1046                          * data link type, so we only let them
1047                          * set it to what it already is.
1048                          */
1049                         if (gndo->ndo_dlt != pcap_datalink(pd)) {
1050                                 error("%s is not one of the DLTs supported by this device\n",
1051                                       gndo->ndo_dltname);
1052                         }
1053 #endif
1054                         (void)fprintf(stderr, "%s: data link type %s\n",
1055                                       program_name, gndo->ndo_dltname);
1056                         (void)fflush(stderr);
1057                 }
1058                 i = pcap_snapshot(pd);
1059                 if (snaplen < i) {
1060                         warning("snaplen raised from %d to %d", snaplen, i);
1061                         snaplen = i;
1062                 }
1063                 if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
1064                         localnet = 0;
1065                         netmask = 0;
1066                         warning("%s", ebuf);
1067                 }
1068         }
1069         if (infile)
1070                 cmdbuf = read_infile(infile);
1071         else
1072                 cmdbuf = copy_argv(&argv[optind]);
1073
1074         if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
1075                 error("%s", pcap_geterr(pd));
1076         if (dflag) {
1077                 bpf_dump(&fcode, dflag);
1078                 pcap_close(pd);
1079                 exit(0);
1080         }
1081         init_addrtoname(localnet, netmask);
1082         init_checksum();
1083
1084 #ifndef WIN32
1085         (void)setsignal(SIGPIPE, cleanup);
1086         (void)setsignal(SIGTERM, cleanup);
1087         (void)setsignal(SIGINT, cleanup);
1088         (void)setsignal(SIGCHLD, child_cleanup);
1089 #endif /* WIN32 */
1090         /* Cooperate with nohup(1) */
1091 #ifndef WIN32
1092         if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL)
1093                 (void)setsignal(SIGHUP, oldhandler);
1094 #endif /* WIN32 */
1095
1096         if (pcap_setfilter(pd, &fcode) < 0)
1097                 error("%s", pcap_geterr(pd));
1098         if (WFileName) {
1099                 pcap_dumper_t *p;
1100                 /* Do not exceed the default NAME_MAX for files. */
1101                 dumpinfo.CurrentFileName = (char *)malloc(NAME_MAX + 1);
1102
1103                 if (dumpinfo.CurrentFileName == NULL)
1104                         error("malloc of dumpinfo.CurrentFileName");
1105
1106                 /* We do not need numbering for dumpfiles if Cflag isn't set. */
1107                 if (Cflag != 0)
1108                   MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, WflagChars);
1109                 else
1110                   MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, 0);
1111
1112                 p = pcap_dump_open(pd, dumpinfo.CurrentFileName);
1113                 if (p == NULL)
1114                         error("%s", pcap_geterr(pd));
1115                 if (Cflag != 0 || Gflag != 0) {
1116                         callback = dump_packet_and_trunc;
1117                         dumpinfo.WFileName = WFileName;
1118                         dumpinfo.pd = pd;
1119                         dumpinfo.p = p;
1120                         pcap_userdata = (u_char *)&dumpinfo;
1121                 } else {
1122                         callback = dump_packet;
1123                         pcap_userdata = (u_char *)p;
1124                 }
1125         } else {
1126                 type = pcap_datalink(pd);
1127                 printinfo.printer = lookup_printer(type);
1128                 if (printinfo.printer == NULL) {
1129                         gndo->ndo_dltname = pcap_datalink_val_to_name(type);
1130                         if (gndo->ndo_dltname != NULL)
1131                                 error("unsupported data link type %s",
1132                                       gndo->ndo_dltname);
1133                         else
1134                                 error("unsupported data link type %d", type);
1135                 }
1136                 callback = print_packet;
1137                 pcap_userdata = (u_char *)&printinfo;
1138         }
1139 #ifndef WIN32
1140         /*
1141          * We cannot do this earlier, because we want to be able to open
1142          * the file (if done) for writing before giving up permissions.
1143          */
1144         if (getuid() == 0 || geteuid() == 0) {
1145                 if (username || chroot_dir)
1146                         droproot(username, chroot_dir);
1147         }
1148 #endif /* WIN32 */
1149 #ifdef SIGINFO
1150         /*
1151          * We can't get statistics when reading from a file rather
1152          * than capturing from a device.
1153          */
1154         if (RFileName == NULL)
1155                 (void)setsignal(SIGINFO, requestinfo);
1156 #endif
1157
1158         if (vflag > 0 && WFileName) {
1159                 /*
1160                  * When capturing to a file, "-v" means tcpdump should,
1161                  * every 10 secodns, "v"erbosely report the number of
1162                  * packets captured.
1163                  */
1164 #ifdef USE_WIN32_MM_TIMER
1165                 /* call verbose_stats_dump() each 1000 +/-100msec */
1166                 timer_id = timeSetEvent(1000, 100, verbose_stats_dump, 0, TIME_PERIODIC);
1167                 setvbuf(stderr, NULL, _IONBF, 0);
1168 #elif defined(HAVE_ALARM)
1169                 (void)setsignal(SIGALRM, verbose_stats_dump);
1170                 alarm(1);
1171 #endif
1172         }
1173
1174 #ifndef WIN32
1175         if (RFileName == NULL) {
1176                 int dlt;
1177                 const char *dlt_name;
1178
1179                 if (!vflag && !WFileName) {
1180                         (void)fprintf(stderr,
1181                             "%s: verbose output suppressed, use -v or -vv for full protocol decode\n",
1182                             program_name);
1183                 } else
1184                         (void)fprintf(stderr, "%s: ", program_name);
1185                 dlt = pcap_datalink(pd);
1186                 dlt_name = pcap_datalink_val_to_name(dlt);
1187                 if (dlt_name == NULL) {
1188                         (void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n",
1189                             device, dlt, snaplen);
1190                 } else {
1191                         (void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n",
1192                             device, dlt_name,
1193                             pcap_datalink_val_to_description(dlt), snaplen);
1194                 }
1195                 (void)fflush(stderr);
1196         }
1197 #endif /* WIN32 */
1198         status = pcap_loop(pd, cnt, callback, pcap_userdata);
1199         if (WFileName == NULL) {
1200                 /*
1201                  * We're printing packets.  Flush the printed output,
1202                  * so it doesn't get intermingled with error output.
1203                  */
1204                 if (status == -2) {
1205                         /*
1206                          * We got interrupted, so perhaps we didn't
1207                          * manage to finish a line we were printing.
1208                          * Print an extra newline, just in case.
1209                          */
1210                         putchar('\n');
1211                 }
1212                 (void)fflush(stdout);
1213         }
1214         if (status == -1) {
1215                 /*
1216                  * Error.  Report it.
1217                  */
1218                 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
1219                     program_name, pcap_geterr(pd));
1220         }
1221         if (RFileName == NULL) {
1222                 /*
1223                  * We're doing a live capture.  Report the capture
1224                  * statistics.
1225                  */
1226                 info(1);
1227         }
1228         pcap_close(pd);
1229         exit(status == -1 ? 1 : 0);
1230 }
1231
1232 /* make a clean exit on interrupts */
1233 static RETSIGTYPE
1234 cleanup(int signo _U_)
1235 {
1236 #ifdef USE_WIN32_MM_TIMER
1237         if (timer_id)
1238                 timeKillEvent(timer_id);
1239         timer_id = 0;
1240 #elif defined(HAVE_ALARM)
1241         alarm(0);
1242 #endif
1243
1244 #ifdef HAVE_PCAP_BREAKLOOP
1245         /*
1246          * We have "pcap_breakloop()"; use it, so that we do as little
1247          * as possible in the signal handler (it's probably not safe
1248          * to do anything with standard I/O streams in a signal handler -
1249          * the ANSI C standard doesn't say it is).
1250          */
1251         pcap_breakloop(pd);
1252 #else
1253         /*
1254          * We don't have "pcap_breakloop()"; this isn't safe, but
1255          * it's the best we can do.  Print the summary if we're
1256          * not reading from a savefile - i.e., if we're doing a
1257          * live capture - and exit.
1258          */
1259         if (pd != NULL && pcap_file(pd) == NULL) {
1260                 /*
1261                  * We got interrupted, so perhaps we didn't
1262                  * manage to finish a line we were printing.
1263                  * Print an extra newline, just in case.
1264                  */
1265                 putchar('\n');
1266                 (void)fflush(stdout);
1267                 info(1);
1268         }
1269         exit(0);
1270 #endif
1271 }
1272
1273 /*
1274   On windows, we do not use a fork, so we do not care less about
1275   waiting a child processes to die
1276  */
1277 #ifndef WIN32
1278 static RETSIGTYPE
1279 child_cleanup(int signo _U_)
1280 {
1281   wait(NULL);
1282 }
1283 #endif /* WIN32 */
1284
1285 static void
1286 info(register int verbose)
1287 {
1288         struct pcap_stat stat;
1289
1290         if (pcap_stats(pd, &stat) < 0) {
1291                 (void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd));
1292                 infoprint = 0;
1293                 return;
1294         }
1295
1296         if (!verbose)
1297                 fprintf(stderr, "%s: ", program_name);
1298
1299         (void)fprintf(stderr, "%u packets captured", packets_captured);
1300         if (!verbose)
1301                 fputs(", ", stderr);
1302         else
1303                 putc('\n', stderr);
1304         (void)fprintf(stderr, "%d packets received by filter", stat.ps_recv);
1305         if (!verbose)
1306                 fputs(", ", stderr);
1307         else
1308                 putc('\n', stderr);
1309         (void)fprintf(stderr, "%d packets dropped by kernel\n", stat.ps_drop);
1310         infoprint = 0;
1311 }
1312
1313 #ifndef WIN32
1314 static void
1315 compress_savefile(const char *filename)
1316 {
1317         if (fork())
1318                 return;
1319         /*
1320          * Set to lowest priority so that this doesn't disturb the capture
1321          */
1322 #ifdef NZERO
1323         setpriority(PRIO_PROCESS, 0, NZERO - 1);
1324 #else
1325         setpriority(PRIO_PROCESS, 0, 19);
1326 #endif
1327         if (execlp(zflag, zflag, filename, NULL) == -1)
1328                 fprintf(stderr,
1329                         "compress_savefile:execlp(%s, %s): %s\n",
1330                         zflag,
1331                         filename,
1332                         strerror(errno));
1333 }
1334 #else  /* WIN32 */
1335 static void
1336 compress_savefile(const char *filename)
1337 {
1338         fprintf(stderr,
1339                 "compress_savefile failed. Functionality not implemented under windows\n");
1340 }
1341 #endif /* WIN32 */
1342
1343 static void
1344 dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1345 {
1346         struct dump_info *dump_info;
1347
1348         ++packets_captured;
1349
1350         ++infodelay;
1351
1352         dump_info = (struct dump_info *)user;
1353
1354         /*
1355          * XXX - this won't force the file to rotate on the specified time
1356          * boundary, but it will rotate on the first packet received after the
1357          * specified Gflag number of seconds. Note: if a Gflag time boundary
1358          * and a Cflag size boundary coincide, the time rotation will occur
1359          * first thereby cancelling the Cflag boundary (since the file should
1360          * be 0).
1361          */
1362         if (Gflag != 0) {
1363                 /* Check if it is time to rotate */
1364                 time_t t;
1365
1366                 /* Get the current time */
1367                 if ((t = time(NULL)) == (time_t)-1) {
1368                         error("dump_and_trunc_packet: can't get current_time: %s",
1369                             pcap_strerror(errno));
1370                 }
1371
1372
1373                 /* If the time is greater than the specified window, rotate */
1374                 if (t - Gflag_time >= Gflag) {
1375                         /* Update the Gflag_time */
1376                         Gflag_time = t;
1377                         /* Update Gflag_count */
1378                         Gflag_count++;
1379                         /*
1380                          * Close the current file and open a new one.
1381                          */
1382                         pcap_dump_close(dump_info->p);
1383
1384                         /*
1385                          * Compress the file we just closed, if the user asked for it
1386                          */
1387                         if (zflag != NULL)
1388                                 compress_savefile(dump_info->CurrentFileName);
1389
1390                         /*
1391                          * Check to see if we've exceeded the Wflag (when
1392                          * not using Cflag).
1393                          */
1394                         if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) {
1395                                 (void)fprintf(stderr, "Maximum file limit reached: %d\n",
1396                                     Wflag);
1397                                 exit(0);
1398                                 /* NOTREACHED */
1399                         }
1400                         if (dump_info->CurrentFileName != NULL)
1401                                 free(dump_info->CurrentFileName);
1402                         /* Allocate space for max filename + \0. */
1403                         dump_info->CurrentFileName = (char *)malloc(NAME_MAX + 1);
1404                         if (dump_info->CurrentFileName == NULL)
1405                                 error("dump_packet_and_trunc: malloc");
1406                         /*
1407                          * This is always the first file in the Cflag
1408                          * rotation: e.g. 0
1409                          * We also don't need numbering if Cflag is not set.
1410                          */
1411                         if (Cflag != 0)
1412                                 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0,
1413                                     WflagChars);
1414                         else
1415                                 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0, 0);
1416
1417                         dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
1418                         if (dump_info->p == NULL)
1419                                 error("%s", pcap_geterr(pd));
1420                 }
1421         }
1422
1423         /*
1424          * XXX - this won't prevent capture files from getting
1425          * larger than Cflag - the last packet written to the
1426          * file could put it over Cflag.
1427          */
1428         if (Cflag != 0 && pcap_dump_ftell(dump_info->p) > Cflag) {
1429                 /*
1430                  * Close the current file and open a new one.
1431                  */
1432                 pcap_dump_close(dump_info->p);
1433
1434                 /*
1435                  * Compress the file we just closed, if the user asked for it
1436                  */
1437                 if (zflag != NULL)
1438                         compress_savefile(dump_info->CurrentFileName);
1439
1440                 Cflag_count++;
1441                 if (Wflag > 0) {
1442                         if (Cflag_count >= Wflag)
1443                                 Cflag_count = 0;
1444                 }
1445                 if (dump_info->CurrentFileName != NULL)
1446                         free(dump_info->CurrentFileName);
1447                 dump_info->CurrentFileName = (char *)malloc(NAME_MAX + 1);
1448                 if (dump_info->CurrentFileName == NULL)
1449                         error("dump_packet_and_trunc: malloc");
1450                 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, Cflag_count, WflagChars);
1451                 dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
1452                 if (dump_info->p == NULL)
1453                         error("%s", pcap_geterr(pd));
1454         }
1455
1456         pcap_dump((u_char *)dump_info->p, h, sp);
1457 #ifdef HAVE_PCAP_DUMP_FLUSH
1458         if (Uflag)
1459                 pcap_dump_flush(dump_info->p);
1460 #endif
1461
1462         --infodelay;
1463         if (infoprint)
1464                 info(0);
1465 }
1466
1467 static void
1468 dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1469 {
1470         ++packets_captured;
1471
1472         ++infodelay;
1473
1474         pcap_dump(user, h, sp);
1475 #ifdef HAVE_PCAP_DUMP_FLUSH
1476         if (Uflag)
1477                 pcap_dump_flush((pcap_dumper_t *)user);
1478 #endif
1479
1480         --infodelay;
1481         if (infoprint)
1482                 info(0);
1483 }
1484
1485 static void
1486 print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1487 {
1488         struct print_info *print_info;
1489         u_int hdrlen;
1490
1491         ++packets_captured;
1492
1493         ++infodelay;
1494         ts_print(&h->ts);
1495
1496         print_info = (struct print_info *)user;
1497
1498         /*
1499          * Some printers want to check that they're not walking off the
1500          * end of the packet.
1501          * Rather than pass it all the way down, we set this global.
1502          */
1503         snapend = sp + h->caplen;
1504
1505         hdrlen = (*print_info->printer)(h, sp);
1506         if (Xflag) {
1507                 /*
1508                  * Print the raw packet data in hex and ASCII.
1509                  */
1510                 if (Xflag > 1) {
1511                         /*
1512                          * Include the link-layer header.
1513                          */
1514                         hex_and_ascii_print("\n\t", sp, h->caplen);
1515                 } else {
1516                         /*
1517                          * Don't include the link-layer header - and if
1518                          * we have nothing past the link-layer header,
1519                          * print nothing.
1520                          */
1521                         if (h->caplen > hdrlen)
1522                                 hex_and_ascii_print("\n\t", sp + hdrlen,
1523                                     h->caplen - hdrlen);
1524                 }
1525         } else if (xflag) {
1526                 /*
1527                  * Print the raw packet data in hex.
1528                  */
1529                 if (xflag > 1) {
1530                         /*
1531                          * Include the link-layer header.
1532                          */
1533                         hex_print("\n\t", sp, h->caplen);
1534                 } else {
1535                         /*
1536                          * Don't include the link-layer header - and if
1537                          * we have nothing past the link-layer header,
1538                          * print nothing.
1539                          */
1540                         if (h->caplen > hdrlen)
1541                                 hex_print("\n\t", sp + hdrlen,
1542                                     h->caplen - hdrlen);
1543                 }
1544         } else if (Aflag) {
1545                 /*
1546                  * Print the raw packet data in ASCII.
1547                  */
1548                 if (Aflag > 1) {
1549                         /*
1550                          * Include the link-layer header.
1551                          */
1552                         ascii_print(sp, h->caplen);
1553                 } else {
1554                         /*
1555                          * Don't include the link-layer header - and if
1556                          * we have nothing past the link-layer header,
1557                          * print nothing.
1558                          */
1559                         if (h->caplen > hdrlen)
1560                                 ascii_print(sp + hdrlen, h->caplen - hdrlen);
1561                 }
1562         }
1563
1564         putchar('\n');
1565
1566         --infodelay;
1567         if (infoprint)
1568                 info(0);
1569 }
1570
1571 #ifdef WIN32
1572         /*
1573          * XXX - there should really be libpcap calls to get the version
1574          * number as a string (the string would be generated from #defines
1575          * at run time, so that it's not generated from string constants
1576          * in the library, as, on many UNIX systems, those constants would
1577          * be statically linked into the application executable image, and
1578          * would thus reflect the version of libpcap on the system on
1579          * which the application was *linked*, not the system on which it's
1580          * *running*.
1581          *
1582          * That routine should be documented, unlike the "version[]"
1583          * string, so that UNIX vendors providing their own libpcaps
1584          * don't omit it (as a couple of vendors have...).
1585          *
1586          * Packet.dll should perhaps also export a routine to return the
1587          * version number of the Packet.dll code, to supply the
1588          * "Wpcap_version" information on Windows.
1589          */
1590         char WDversion[]="current-cvs.tcpdump.org";
1591 #if !defined(HAVE_GENERATED_VERSION)
1592         char version[]="current-cvs.tcpdump.org";
1593 #endif
1594         char pcap_version[]="current-cvs.tcpdump.org";
1595         char Wpcap_version[]="3.1";
1596 #endif
1597
1598 /*
1599  * By default, print the specified data out in hex and ASCII.
1600  */
1601 static void
1602 ndo_default_print(netdissect_options *ndo _U_, const u_char *bp, u_int length)
1603 {
1604         hex_and_ascii_print("\n\t", bp, length); /* pass on lf and identation string */
1605 }
1606
1607 void
1608 default_print(const u_char *bp, u_int length)
1609 {
1610         ndo_default_print(gndo, bp, length);
1611 }
1612
1613 #ifdef SIGINFO
1614 RETSIGTYPE requestinfo(int signo _U_)
1615 {
1616         if (infodelay)
1617                 ++infoprint;
1618         else
1619                 info(0);
1620 }
1621 #endif
1622
1623 /*
1624  * Called once each second in verbose mode while dumping to file
1625  */
1626 #ifdef USE_WIN32_MM_TIMER
1627 void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_,
1628                                   DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_)
1629 {
1630         struct pcap_stat stat;
1631
1632         if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
1633                 fprintf(stderr, "Got %u\r", packets_captured);
1634 }
1635 #elif defined(HAVE_ALARM)
1636 static void verbose_stats_dump(int sig _U_)
1637 {
1638         struct pcap_stat stat;
1639
1640         if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
1641                 fprintf(stderr, "Got %u\r", packets_captured);
1642         alarm(1);
1643 }
1644 #endif
1645
1646 static void
1647 usage(void)
1648 {
1649         extern char version[];
1650 #ifndef HAVE_PCAP_LIB_VERSION
1651 #if defined(WIN32) || defined(HAVE_PCAP_VERSION)
1652         extern char pcap_version[];
1653 #else /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
1654         static char pcap_version[] = "unknown";
1655 #endif /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
1656 #endif /* HAVE_PCAP_LIB_VERSION */
1657
1658 #ifdef HAVE_PCAP_LIB_VERSION
1659 #ifdef WIN32
1660         (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
1661 #else /* WIN32 */
1662         (void)fprintf(stderr, "%s version %s\n", program_name, version);
1663 #endif /* WIN32 */
1664         (void)fprintf(stderr, "%s\n",pcap_lib_version());
1665 #else /* HAVE_PCAP_LIB_VERSION */
1666 #ifdef WIN32
1667         (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
1668         (void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version);
1669 #else /* WIN32 */
1670         (void)fprintf(stderr, "%s version %s\n", program_name, version);
1671         (void)fprintf(stderr, "libpcap version %s\n", pcap_version);
1672 #endif /* WIN32 */
1673 #endif /* HAVE_PCAP_LIB_VERSION */
1674         (void)fprintf(stderr,
1675 "Usage: %s [-aAd" D_FLAG "ef" I_FLAG "KlLnNOpqRStu" U_FLAG "vxX]" B_FLAG_USAGE " [ -c count ]\n", program_name);
1676         (void)fprintf(stderr,
1677 "\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n");
1678         (void)fprintf(stderr,
1679 "\t\t[ -i interface ] [ -M secret ] [ -r file ]\n");
1680         (void)fprintf(stderr,
1681 "\t\t[ -s snaplen ] [ -T type ] [ -w file ] [ -W filecount ]\n");
1682         (void)fprintf(stderr,
1683 "\t\t[ -y datalinktype ] [ -z command ] [ -Z user ]\n");
1684         (void)fprintf(stderr,
1685 "\t\t[ expression ]\n");
1686         exit(1);
1687 }
1688
1689
1690
1691 /* VARARGS */
1692 static void
1693 ndo_error(netdissect_options *ndo _U_, const char *fmt, ...)
1694 {
1695         va_list ap;
1696
1697         (void)fprintf(stderr, "%s: ", program_name);
1698         va_start(ap, fmt);
1699         (void)vfprintf(stderr, fmt, ap);
1700         va_end(ap);
1701         if (*fmt) {
1702                 fmt += strlen(fmt);
1703                 if (fmt[-1] != '\n')
1704                         (void)fputc('\n', stderr);
1705         }
1706         exit(1);
1707         /* NOTREACHED */
1708 }
1709
1710 /* VARARGS */
1711 static void
1712 ndo_warning(netdissect_options *ndo _U_, const char *fmt, ...)
1713 {
1714         va_list ap;
1715
1716         (void)fprintf(stderr, "%s: WARNING: ", program_name);
1717         va_start(ap, fmt);
1718         (void)vfprintf(stderr, fmt, ap);
1719         va_end(ap);
1720         if (*fmt) {
1721                 fmt += strlen(fmt);
1722                 if (fmt[-1] != '\n')
1723                         (void)fputc('\n', stderr);
1724         }
1725 }