The Tcpdump Group git mirrors - tcpdump/blob - 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[] =
  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[] =
  33     "@(#) $Header: /tcpdump/master/tcpdump/tcpdump.c,v 1.182 2002-08-03 23:16:57 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 #include <pcap.h>
  60 #include <signal.h>
  61 #include <stdio.h>
  62 #include <stdlib.h>
  63 #include <string.h>
  64
  65
  66 #include "interface.h"
  67 #include "addrtoname.h"
  68 #include "machdep.h"
  69 #include "setsignal.h"
  70 #include "gmt2local.h"
  71
  72 int aflag;                      /* translate network and broadcast addresses */
  73 int dflag;                      /* print filter code */
  74 int eflag;                      /* print ethernet header */
  75 int fflag;                      /* don't translate "foreign" IP address */
  76 int nflag;                      /* leave addresses as numbers */
  77 int Nflag;                      /* remove domains from printed host names */
  78 int Oflag = 1;                  /* run filter code optimizer */
  79 int pflag;                      /* don't go promiscuous */
  80 int qflag;                      /* quick (shorter) output */
  81 int Rflag = 1;                  /* print sequence # field in AH/ESP*/
  82 int sflag = 0;                  /* use the libsmi to translate OIDs */
  83 int Sflag;                      /* print raw TCP sequence numbers */
  84 int tflag = 1;                  /* print packet arrival time */
  85 int uflag = 0;                  /* Print undecoded NFS handles */
  86 int vflag;                      /* verbose */
  87 int xflag;                      /* print packet in hex */
  88 int Xflag;                      /* print packet in ascii as well as hex */
  89 off_t Cflag = 0;                /* rotate dump files after this many bytes */
  90 int Aflag = 0;                  /* print packet only in ascii observing LF, CR, TAB, SPACE */
  91
  92 char *espsecret = NULL;         /* ESP secret key */
  93
  94 int packettype;
  95
  96 int infodelay;
  97 int infoprint;
  98
  99 char *program_name;
 100
 101 int32_t thiszone;               /* seconds offset from gmt to local time */
 102
 103 /* Forwards */
 104 static RETSIGTYPE cleanup(int);
 105 static void usage(void) __attribute__((noreturn));
 106
 107 static void dump_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *);
 108
 109 #ifdef SIGINFO
 110 RETSIGTYPE requestinfo(int);
 111 #endif
 112
 113 /* Length of saved portion of packet. */
 114 int snaplen = DEFAULT_SNAPLEN;
 115
 116 struct printer {
 117         pcap_handler f;
 118         int type;
 119 };
 120
 121 static struct printer printers[] = {
 122         { arcnet_if_print,      DLT_ARCNET },
 123         { ether_if_print,       DLT_EN10MB },
 124         { token_if_print,       DLT_IEEE802 },
 125 #ifdef DLT_LANE8023
 126         { lane_if_print,        DLT_LANE8023 },
 127 #endif
 128 #ifdef DLT_CIP
 129         { cip_if_print,         DLT_CIP },
 130 #endif
 131 #ifdef DLT_ATM_CLIP
 132         { cip_if_print,         DLT_ATM_CLIP },
 133 #endif
 134         { sl_if_print,          DLT_SLIP },
 135         { sl_bsdos_if_print,    DLT_SLIP_BSDOS },
 136         { ppp_if_print,         DLT_PPP },
 137         { ppp_bsdos_if_print,   DLT_PPP_BSDOS },
 138         { fddi_if_print,        DLT_FDDI },
 139         { null_if_print,        DLT_NULL },
 140 #ifdef DLT_LOOP
 141         { null_if_print,        DLT_LOOP },
 142 #endif
 143         { raw_if_print,         DLT_RAW },
 144         { atm_if_print,         DLT_ATM_RFC1483 },
 145 #ifdef DLT_C_HDLC
 146         { chdlc_if_print,       DLT_C_HDLC },
 147 #endif
 148 #ifdef DLT_HDLC
 149         { chdlc_if_print,       DLT_HDLC },
 150 #endif
 151 #ifdef DLT_PPP_SERIAL
 152         { ppp_hdlc_if_print,    DLT_PPP_SERIAL },
 153 #endif
 154 #ifdef DLT_PPP_ETHER
 155         { pppoe_if_print,       DLT_PPP_ETHER },
 156 #endif
 157 #ifdef DLT_LINUX_SLL
 158         { sll_if_print,         DLT_LINUX_SLL },
 159 #endif
 160 #ifdef DLT_IEEE802_11
 161         { ieee802_11_if_print,  DLT_IEEE802_11},
 162 #endif
 163 #ifdef DLT_LTALK
 164         { ltalk_if_print,       DLT_LTALK },
 165 #endif
 166 #ifdef DLT_PFLOG
 167         { pflog_if_print,       DLT_PFLOG },
 168 #endif
 169 #ifdef DLT_FR
 170         { fr_if_print,          DLT_FR },
 171 #endif
 172 #ifdef DLT_FRELAY
 173         { fr_if_print,          DLT_FRELAY },
 174 #endif
 175 #ifdef DLT_SUNATM
 176         { sunatm_if_print,      DLT_SUNATM },
 177 #endif
 178         { NULL,                 0 },
 179 };
 180
 181 static pcap_handler
 182 lookup_printer(int type)
 183 {
 184         struct printer *p;
 185
 186         for (p = printers; p->f; ++p)
 187                 if (type == p->type)
 188                         return p->f;
 189
 190         error("unknown data link type %d", type);
 191         /* NOTREACHED */
 192 }
 193
 194 static pcap_t *pd;
 195
 196 extern int optind;
 197 extern int opterr;
 198 extern char *optarg;
 199
 200 struct dump_info {
 201         char    *WFileName;
 202         pcap_t  *pd;
 203         pcap_dumper_t *p;
 204 };
 205
 206 int
 207 main(int argc, char **argv)
 208 {
 209         register int cnt, op, i;
 210         bpf_u_int32 localnet, netmask;
 211         register char *cp, *infile, *cmdbuf, *device, *RFileName, *WFileName;
 212         pcap_handler printer;
 213         struct bpf_program fcode;
 214 #ifndef WIN32
 215         RETSIGTYPE (*oldhandler)(int);
 216 #endif
 217         struct dump_info dumpinfo;
 218         u_char *pcap_userdata;
 219         char ebuf[PCAP_ERRBUF_SIZE];
 220 #ifdef HAVE_PCAP_FINDALLDEVS
 221         pcap_if_t *devpointer;
 222         int devnum;
 223 #endif
 224 #ifdef WIN32
 225         int ii;
 226         DWORD dwVersion;
 227         DWORD dwWindowsMajorVersion;
 228         u_int UserBufferSize=1000000;
 229 #endif
 230
 231 #ifdef WIN32
 232         dwVersion=GetVersion();         /* get the OS version */
 233         dwWindowsMajorVersion =  (DWORD)(LOBYTE(LOWORD(dwVersion)));
 234         if(wsockinit()!=0) return 1;
 235 #endif /* WIN32 */
 236
 237         cnt = -1;
 238         device = NULL;
 239         infile = NULL;
 240         RFileName = NULL;
 241         WFileName = NULL;
 242         if ((cp = strrchr(argv[0], '/')) != NULL)
 243                 program_name = cp + 1;
 244         else
 245                 program_name = argv[0];
 246
 247         if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
 248                 error("%s", ebuf);
 249
 250 #ifdef LIBSMI
 251         smiInit("tcpdump");
 252 #endif
 253
 254         opterr = 0;
 255         while (
 256 #ifdef WIN32
 257             (op = getopt(argc, argv, "aB:c:C:dDeE:fF:i:lm:nNOpqr:Rs:StT:uvw:xXY")) != -1)
 258 #else /* WIN32 */
 259 #ifdef HAVE_PCAP_FINDALLDEVS
 260             (op = getopt(argc, argv, "ac:C:dDeE:fF:i:lm:nNOpqr:Rs:StT:uvw:xXY")) != -1)
 261 #else /* HAVE_PCAP_FINDALLDEVS */
 262             (op = getopt(argc, argv, "ac:C:deE:fF:i:lm:nNOpqr:Rs:StT:uvw:xXY")) != -1)
 263 #endif /* HAVE_PCAP_FINDALLDEVS */
 264 #endif /* WIN32 */
 265                 switch (op) {
 266
 267                 case 'a':
 268                         ++aflag;
 269                         break;
 270
 271                case 'A':
 272                        ++xflag;
 273                        ++Xflag;
 274                        ++Aflag;
 275                        break;
 276
 277 #ifdef WIN32
 278                 case 'B':
 279                         UserBufferSize = atoi(optarg)*1024;
 280                         if (UserBufferSize < 0)
 281                                 error("invalid packet buffer size %s", optarg);
 282                         break;
 283 #endif /* WIN32 */
 284
 285                 case 'c':
 286                         cnt = atoi(optarg);
 287                         if (cnt <= 0)
 288                                 error("invalid packet count %s", optarg);
 289                         break;
 290
 291                 case 'C':
 292                         Cflag = atoi(optarg) * 1000000;
 293                         if (Cflag < 0)
 294                                 error("invalid file size %s", optarg);
 295                         break;
 296
 297                 case 'd':
 298                         ++dflag;
 299                         break;
 300
 301 #ifdef HAVE_PCAP_FINDALLDEVS
 302                 case 'D':
 303                         if (pcap_findalldevs(&devpointer, ebuf) < 0)
 304                                 error("%s", ebuf);
 305                         else {
 306                                 for (i = 0; devpointer != 0; i++) {
 307                                         printf("%d.%s", i+1, devpointer->name);
 308                                         if (devpointer->description != NULL)
 309                                                 printf(" (%s)", devpointer->description);
 310                                         printf("\n");
 311                                         devpointer = devpointer->next;
 312                                 }
 313                         }
 314                         return 0;
 315 #endif /* HAVE_PCAP_FINDALLDEVS */
 316
 317                 case 'e':
 318                         ++eflag;
 319                         break;
 320
 321                 case 'E':
 322 #ifndef HAVE_LIBCRYPTO
 323                         warning("crypto code not compiled in");
 324 #endif
 325                         espsecret = optarg;
 326                         break;
 327
 328                 case 'f':
 329                         ++fflag;
 330                         break;
 331
 332                 case 'F':
 333                         infile = optarg;
 334                         break;
 335
 336                 case 'i':
 337                         if (optarg[0] == '0' && optarg[1] == 0)
 338                                 error("Invalid adapter index");
 339
 340 #ifdef HAVE_PCAP_FINDALLDEVS
 341                         /*
 342                          * If the argument is a number, treat it as
 343                          * an index into the list of adapters, as
 344                          * printed by "tcpdump -D".
 345                          *
 346                          * This should be OK on UNIX systems, as interfaces
 347                          * shouldn't have names that begin with digits.
 348                          * It can be useful on Windows, where more than
 349                          * one interface can have the same name.
 350                          */
 351                         if ((devnum = atoi(optarg)) != 0) {
 352                                 if (devnum < 0)
 353                                         error("Invalid adapter index");
 354
 355                                 if (pcap_findalldevs(&devpointer, ebuf) < 0)
 356                                         error("%s", ebuf);
 357                                 else {
 358                                         for (i = 0; i < devnum-1; i++){
 359                                                 devpointer = devpointer->next;
 360                                                 if (devpointer == NULL)
 361                                                         error("Invalid adapter index");
 362                                         }
 363                                 }
 364                                 device = devpointer->name;
 365                                 break;
 366                         }
 367 #endif /* HAVE_PCAP_FINDALLDEVS */
 368                         device = optarg;
 369                         break;
 370
 371                 case 'l':
 372 #ifdef HAVE_SETLINEBUF
 373                         setlinebuf(stdout);
 374 #else
 375                         setvbuf(stdout, NULL, _IOLBF, 0);
 376 #endif
 377                         break;
 378
 379                 case 'n':
 380                         ++nflag;
 381                         break;
 382
 383                 case 'N':
 384                         ++Nflag;
 385                         break;
 386
 387                 case 'm':
 388 #ifdef LIBSMI
 389                         if (smiLoadModule(optarg) == 0) {
 390                                 error("could not load MIB module %s", optarg);
 391                         }
 392                         sflag = 1;
 393 #else
 394                         (void)fprintf(stderr, "%s: ignoring option `-m %s' ",
 395                                       program_name, optarg);
 396                         (void)fprintf(stderr, "(no libsmi support)\n");
 397 #endif
 398
 399                 case 'O':
 400                         Oflag = 0;
 401                         break;
 402
 403                 case 'p':
 404                         ++pflag;
 405                         break;
 406
 407                 case 'q':
 408                         ++qflag;
 409                         break;
 410
 411                 case 'r':
 412                         RFileName = optarg;
 413                         break;
 414
 415                 case 'R':
 416                         Rflag = 0;
 417                         break;
 418
 419                 case 's': {
 420                         char *end;
 421
 422                         snaplen = strtol(optarg, &end, 0);
 423                         if (optarg == end || *end != '\0'
 424                             || snaplen < 0 || snaplen > 65535)
 425                                 error("invalid snaplen %s", optarg);
 426                         else if (snaplen == 0)
 427                                 snaplen = 65535;
 428                         break;
 429                 }
 430
 431                 case 'S':
 432                         ++Sflag;
 433                         break;
 434
 435                 case 't':
 436                         --tflag;
 437                         break;
 438
 439                 case 'T':
 440                         if (strcasecmp(optarg, "vat") == 0)
 441                                 packettype = PT_VAT;
 442                         else if (strcasecmp(optarg, "wb") == 0)
 443                                 packettype = PT_WB;
 444                         else if (strcasecmp(optarg, "rpc") == 0)
 445                                 packettype = PT_RPC;
 446                         else if (strcasecmp(optarg, "rtp") == 0)
 447                                 packettype = PT_RTP;
 448                         else if (strcasecmp(optarg, "rtcp") == 0)
 449                                 packettype = PT_RTCP;
 450                         else if (strcasecmp(optarg, "snmp") == 0)
 451                                 packettype = PT_SNMP;
 452                         else if (strcasecmp(optarg, "cnfp") == 0)
 453                                 packettype = PT_CNFP;
 454                         else
 455                                 error("unknown packet type `%s'", optarg);
 456                         break;
 457
 458                 case 'u':
 459                         ++uflag;
 460                         break;
 461
 462                 case 'v':
 463                         ++vflag;
 464                         break;
 465
 466                 case 'w':
 467                         WFileName = optarg;
 468                         break;
 469
 470                 case 'x':
 471                         ++xflag;
 472                         break;
 473
 474                 case 'X':
 475                         ++xflag;
 476                         ++Xflag;
 477                         break;
 478
 479 #ifdef YYDEBUG
 480                 case 'Y':
 481                         {
 482                         /* Undocumented flag */
 483                         extern int yydebug;
 484                         yydebug = 1;
 485                         }
 486                         break;
 487 #endif
 488                 default:
 489                         usage();
 490                         /* NOTREACHED */
 491                 }
 492
 493         if (aflag && nflag)
 494                 error("-a and -n options are incompatible");
 495
 496         if (tflag > 0)
 497                 thiszone = gmt2local(0);
 498
 499         if (RFileName != NULL) {
 500                 /*
 501                  * We don't need network access, so set it back to the user id.
 502                  * Also, this prevents the user from reading anyone's
 503                  * trace file.
 504                  */
 505 #ifndef WIN32
 506                 setuid(getuid());
 507 #endif /* WIN32 */
 508
 509                 pd = pcap_open_offline(RFileName, ebuf);
 510                 if (pd == NULL)
 511                         error("%s", ebuf);
 512                 localnet = 0;
 513                 netmask = 0;
 514                 if (fflag != 0)
 515                         error("-f and -r options are incompatible");
 516         } else {
 517                 if (device == NULL) {
 518                         device = pcap_lookupdev(ebuf);
 519                         if (device == NULL)
 520                                 error("%s", ebuf);
 521                 }
 522 #ifdef WIN32
 523                 else
 524                 {
 525                         if (!(dwVersion >= 0x80000000 && dwWindowsMajorVersion >= 4))                   /* Windows '95 */
 526                         {
 527                                 if(device[1]!=0)
 528                                         device=(char*)SChar2WChar(device);
 529                         }
 530                         else{
 531                                 for (ii=0;ii<(signed)strlen(device);ii++)
 532                                 for (ii=strlen(device)-1;ii>0&&(device[ii]==' '||device[ii]=='\t');ii--)device[ii]='\0';
 533                                 for (ii=0;ii<(signed)strlen(device)&&(device[ii]==' '||device[ii]=='\t');ii++);
 534                                 strcpy(device,device+ii);
 535                         }
 536                 }
 537                 PrintCapBegins (program_name,device);
 538 #endif /* WIN32 */
 539                 *ebuf = '\0';
 540                 pd = pcap_open_live(device, snaplen, !pflag, 1000, ebuf);
 541                 if (pd == NULL)
 542                         error("%s", ebuf);
 543                 else if (*ebuf)
 544                         warning("%s", ebuf);
 545 #ifdef WIN32
 546                 if(UserBufferSize != 1000000)
 547                         if(pcap_setbuff(pd, UserBufferSize)==-1){
 548                                 error("%s", pcap_geterr(pd));
 549                         }
 550 #endif /* WIN32 */
 551                 i = pcap_snapshot(pd);
 552                 if (snaplen < i) {
 553                         warning("snaplen raised from %d to %d", snaplen, i);
 554                         snaplen = i;
 555                 }
 556                 if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
 557                         localnet = 0;
 558                         netmask = 0;
 559                         warning("%s", ebuf);
 560                 }
 561                 /*
 562                  * Let user own process after socket has been opened.
 563                  */
 564 #ifndef WIN32
 565                 setuid(getuid());
 566 #endif /* WIN32 */
 567         }
 568         if (infile)
 569                 cmdbuf = read_infile(infile);
 570         else
 571                 cmdbuf = copy_argv(&argv[optind]);
 572
 573         if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
 574                 error("%s", pcap_geterr(pd));
 575         if (dflag) {
 576                 bpf_dump(&fcode, dflag);
 577 #ifdef WIN32
 578             pcap_close(pd);
 579 #endif /* WIN32 */
 580                 exit(0);
 581         }
 582         init_addrtoname(localnet, netmask);
 583
 584         (void)setsignal(SIGTERM, cleanup);
 585         (void)setsignal(SIGINT, cleanup);
 586         /* Cooperate with nohup(1) */
 587 #ifndef WIN32
 588         if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL)
 589                 (void)setsignal(SIGHUP, oldhandler);
 590 #endif /* WIN32 */
 591
 592         if (pcap_setfilter(pd, &fcode) < 0)
 593                 error("%s", pcap_geterr(pd));
 594         if (WFileName) {
 595                 pcap_dumper_t *p = pcap_dump_open(pd, WFileName);
 596                 if (p == NULL)
 597                         error("%s", pcap_geterr(pd));
 598                 if (Cflag != 0) {
 599                         printer = dump_and_trunc;
 600                         dumpinfo.WFileName = WFileName;
 601                         dumpinfo.pd = pd;
 602                         dumpinfo.p = p;
 603                         pcap_userdata = (u_char *)&dumpinfo;
 604                 } else {
 605                         printer = pcap_dump;
 606                         pcap_userdata = (u_char *)p;
 607                 }
 608         } else {
 609                 printer = lookup_printer(pcap_datalink(pd));
 610                 pcap_userdata = 0;
 611 #ifdef SIGINFO
 612                 (void)setsignal(SIGINFO, requestinfo);
 613 #endif
 614         }
 615 #ifndef WIN32
 616         if (RFileName == NULL) {
 617                 (void)fprintf(stderr, "%s: listening on %s\n",
 618                     program_name, device);
 619                 (void)fflush(stderr);
 620         }
 621 #endif /* WIN32 */
 622         if (pcap_loop(pd, cnt, printer, pcap_userdata) < 0) {
 623                 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
 624                     program_name, pcap_geterr(pd));
 625                 cleanup(0);
 626                 pcap_close(pd);
 627                 exit(1);
 628         }
 629         if (RFileName == NULL)
 630                 info(1);
 631         pcap_close(pd);
 632         exit(0);
 633 }
 634
 635 /* make a clean exit on interrupts */
 636 static RETSIGTYPE
 637 cleanup(int signo)
 638 {
 639
 640         /* Can't print the summary if reading from a savefile */
 641         if (pd != NULL && pcap_file(pd) == NULL) {
 642                 (void)fflush(stdout);
 643                 putc('\n', stderr);
 644                 info(1);
 645         }
 646         if (signo)
 647                 exit(0);
 648 }
 649
 650 void
 651 info(register int verbose)
 652 {
 653         struct pcap_stat stat;
 654
 655         if (pcap_stats(pd, &stat) < 0) {
 656                 (void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd));
 657                 return;
 658         }
 659
 660         if (!verbose)
 661                 fprintf(stderr, "%s: ", program_name);
 662
 663         (void)fprintf(stderr, "%d packets received by filter", stat.ps_recv);
 664         if (!verbose)
 665                 fputs(", ", stderr);
 666         else
 667                 putc('\n', stderr);
 668         (void)fprintf(stderr, "%d packets dropped by kernel\n", stat.ps_drop);
 669         infoprint = 0;
 670 }
 671
 672 static void
 673 reverse(char *s)
 674 {
 675         int i, j, c;
 676
 677         for (i = 0, j = strlen(s) - 1; i < j; i++, j--) {
 678                 c = s[i];
 679                 s[i] = s[j];
 680                 s[j] = c;
 681         }
 682 }
 683
 684
 685 static void
 686 swebitoa(unsigned int n, char *s)
 687 {
 688         unsigned int i;
 689
 690         i = 0;
 691         do {
 692                 s[i++] = n % 10 + '0';
 693         } while ((n /= 10) > 0);
 694
 695         s[i] = '\0';
 696         reverse(s);
 697 }
 698
 699 static void
 700 dump_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 701 {
 702         struct dump_info *info;
 703         static uint cnt = 2;
 704         char *name;
 705
 706         info = (struct dump_info *)user;
 707
 708         /*
 709          * XXX - this won't prevent capture files from getting
 710          * larger than Cflag - the last packet written to the
 711          * file could put it over Cflag.
 712          */
 713         if (ftell((FILE *)info->p) > Cflag) {
 714                 name = (char *) malloc(strlen(info->WFileName) + 4);
 715                 if (name == NULL)
 716                         error("dump_and_trunc: malloc");
 717                 strcpy(name, info->WFileName);
 718                 swebitoa(cnt, name + strlen(info->WFileName));
 719                 cnt++;
 720                 pcap_dump_close(info->p);
 721                 info->p = pcap_dump_open(info->pd, name);
 722                 free(name);
 723                 if (info->p == NULL)
 724                         error("%s", pcap_geterr(pd));
 725         }
 726
 727         pcap_dump((u_char *)info->p, h, sp);
 728 }
 729
 730 /* Like default_print() but data need not be aligned */
 731 void
 732 default_print_unaligned(register const u_char *cp, register u_int length)
 733 {
 734         register u_int i, s;
 735         register int nshorts;
 736
 737         if (Xflag) {
 738                 ascii_print(cp, length);
 739                 return;
 740         }
 741         nshorts = (u_int) length / sizeof(u_short);
 742         i = 0;
 743         while (--nshorts >= 0) {
 744                 if ((i++ % 8) == 0)
 745                         (void)printf("\n\t\t\t");
 746                 s = *cp++;
 747                 (void)printf(" %02x%02x", s, *cp++);
 748         }
 749         if (length & 1) {
 750                 if ((i % 8) == 0)
 751                         (void)printf("\n\t\t\t");
 752                 (void)printf(" %02x", *cp);
 753         }
 754 }
 755
 756 #ifdef WIN32
 757         char WDversion[]="current-cvs.tcpdump.org";
 758         char version[]="current-cvs.tcpdump.org";
 759         char pcap_version[]="current-cvs.tcpdump.org";
 760         char Wpcap_version[]="3.0 alpha";
 761 #endif
 762
 763 /*
 764  * By default, print the packet out in hex.
 765  */
 766 void
 767 default_print(register const u_char *bp, register u_int length)
 768 {
 769         default_print_unaligned(bp, length);
 770 }
 771
 772 #ifdef SIGINFO
 773 RETSIGTYPE requestinfo(int signo)
 774 {
 775         if (infodelay)
 776                 ++infoprint;
 777         else
 778                 info(0);
 779 }
 780 #endif
 781
 782 static void
 783 usage(void)
 784 {
 785         extern char version[];
 786         extern char pcap_version[];
 787
 788 #ifdef WIN32
 789         (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
 790         (void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version);
 791 #else
 792         (void)fprintf(stderr, "%s version %s\n", program_name, version);
 793         (void)fprintf(stderr, "libpcap version %s\n", pcap_version);
 794 #endif /* WIN32 */
 795         (void)fprintf(stderr,
 796 #ifdef WIN32
 797 "Usage: %s [-adDeflnNOpqStuvxX] [-B size] [-c count] [ -C file_size ]\n", program_name);
 798 #else /* WIN32 */
 799 #ifdef HAVE_PCAP_FINDALLDEVS
 800 "Usage: %s [-adDeflnNOpqStuvxX] [-c count] [ -C file_size ]\n", program_name);
 801 #else /* HAVE_PCAP_FINDALLDEVS */
 802 "Usage: %s [-adeflnNOpqStuvxX] [-c count] [ -C file_size ]\n", program_name);
 803 #endif /* HAVE_PCAP_FINDALLDEVS */
 804 #endif /* WIN32 */
 805         (void)fprintf(stderr,
 806 "\t\t[ -F file ] [ -i interface ] [ -r file ] [ -s snaplen ]\n");
 807         (void)fprintf(stderr,
 808 "\t\t[ -T type ] [ -w file ] [ -E algo:secret ] [ expression ]\n");
 809         exit(1);
 810 }