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 1.187 2002-10-18 09:17:48 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 #ifdef DLT_IP_OVER_FC
 179         { ipfc_if_print,        DLT_IP_OVER_FC },
 180 #endif
 181         { NULL,                 0 },
 182 };
 183
 184 static pcap_handler
 185 lookup_printer(int type)
 186 {
 187         struct printer *p;
 188
 189         for (p = printers; p->f; ++p)
 190                 if (type == p->type)
 191                         return p->f;
 192
 193         error("unknown data link type %d", type);
 194         /* NOTREACHED */
 195 }
 196
 197 static pcap_t *pd;
 198
 199 extern int optind;
 200 extern int opterr;
 201 extern char *optarg;
 202
 203 struct dump_info {
 204         char    *WFileName;
 205         pcap_t  *pd;
 206         pcap_dumper_t *p;
 207 };
 208
 209 int
 210 main(int argc, char **argv)
 211 {
 212         register int cnt, op, i;
 213         bpf_u_int32 localnet, netmask;
 214         register char *cp, *infile, *cmdbuf, *device, *RFileName, *WFileName;
 215         pcap_handler printer;
 216         struct bpf_program fcode;
 217 #ifndef WIN32
 218         RETSIGTYPE (*oldhandler)(int);
 219 #endif
 220         struct dump_info dumpinfo;
 221         u_char *pcap_userdata;
 222         char ebuf[PCAP_ERRBUF_SIZE];
 223 #ifdef HAVE_PCAP_FINDALLDEVS
 224         pcap_if_t *devpointer;
 225         int devnum;
 226 #endif
 227 #ifdef WIN32
 228         DWORD dwVersion;
 229         DWORD dwWindowsMajorVersion;
 230         u_int UserBufferSize=1000000;
 231 #endif
 232
 233 #ifdef WIN32
 234         dwVersion=GetVersion();         /* get the OS version */
 235         dwWindowsMajorVersion =  (DWORD)(LOBYTE(LOWORD(dwVersion)));
 236         if(wsockinit()!=0) return 1;
 237 #endif /* WIN32 */
 238
 239         cnt = -1;
 240         device = NULL;
 241         infile = NULL;
 242         RFileName = NULL;
 243         WFileName = NULL;
 244         if ((cp = strrchr(argv[0], '/')) != NULL)
 245                 program_name = cp + 1;
 246         else
 247                 program_name = argv[0];
 248
 249         if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
 250                 error("%s", ebuf);
 251
 252 #ifdef LIBSMI
 253         smiInit("tcpdump");
 254 #endif
 255
 256         opterr = 0;
 257         while (
 258 #ifdef WIN32
 259             (op = getopt(argc, argv, "aAB:c:C:dDeE:fF:i:lm:nNOpqr:Rs:StT:uvw:xXY")) != -1)
 260 #else /* WIN32 */
 261 #ifdef HAVE_PCAP_FINDALLDEVS
 262             (op = getopt(argc, argv, "aAc:C:dDeE:fF:i:lm:nNOpqr:Rs:StT:uvw:xXY")) != -1)
 263 #else /* HAVE_PCAP_FINDALLDEVS */
 264             (op = getopt(argc, argv, "aAc:C:deE:fF:i:lm:nNOpqr:Rs:StT:uvw:xXY")) != -1)
 265 #endif /* HAVE_PCAP_FINDALLDEVS */
 266 #endif /* WIN32 */
 267                 switch (op) {
 268
 269                 case 'a':
 270                         ++aflag;
 271                         break;
 272
 273                case 'A':
 274                        ++xflag;
 275                        ++Xflag;
 276                        ++Aflag;
 277                        break;
 278
 279 #ifdef WIN32
 280                 case 'B':
 281                         UserBufferSize = atoi(optarg)*1024;
 282                         if (UserBufferSize < 0)
 283                                 error("invalid packet buffer size %s", optarg);
 284                         break;
 285 #endif /* WIN32 */
 286
 287                 case 'c':
 288                         cnt = atoi(optarg);
 289                         if (cnt <= 0)
 290                                 error("invalid packet count %s", optarg);
 291                         break;
 292
 293                 case 'C':
 294                         Cflag = atoi(optarg) * 1000000;
 295                         if (Cflag < 0)
 296                                 error("invalid file size %s", optarg);
 297                         break;
 298
 299                 case 'd':
 300                         ++dflag;
 301                         break;
 302
 303 #ifdef HAVE_PCAP_FINDALLDEVS
 304                 case 'D':
 305                         if (pcap_findalldevs(&devpointer, ebuf) < 0)
 306                                 error("%s", ebuf);
 307                         else {
 308                                 for (i = 0; devpointer != 0; i++) {
 309                                         printf("%d.%s", i+1, devpointer->name);
 310                                         if (devpointer->description != NULL)
 311                                                 printf(" (%s)", devpointer->description);
 312                                         printf("\n");
 313                                         devpointer = devpointer->next;
 314                                 }
 315                         }
 316                         return 0;
 317 #endif /* HAVE_PCAP_FINDALLDEVS */
 318
 319                 case 'e':
 320                         ++eflag;
 321                         break;
 322
 323                 case 'E':
 324 #ifndef HAVE_LIBCRYPTO
 325                         warning("crypto code not compiled in");
 326 #endif
 327                         espsecret = optarg;
 328                         break;
 329
 330                 case 'f':
 331                         ++fflag;
 332                         break;
 333
 334                 case 'F':
 335                         infile = optarg;
 336                         break;
 337
 338                 case 'i':
 339                         if (optarg[0] == '0' && optarg[1] == 0)
 340                                 error("Invalid adapter index");
 341
 342 #ifdef HAVE_PCAP_FINDALLDEVS
 343                         /*
 344                          * If the argument is a number, treat it as
 345                          * an index into the list of adapters, as
 346                          * printed by "tcpdump -D".
 347                          *
 348                          * This should be OK on UNIX systems, as interfaces
 349                          * shouldn't have names that begin with digits.
 350                          * It can be useful on Windows, where more than
 351                          * one interface can have the same name.
 352                          */
 353                         if ((devnum = atoi(optarg)) != 0) {
 354                                 if (devnum < 0)
 355                                         error("Invalid adapter index");
 356
 357                                 if (pcap_findalldevs(&devpointer, ebuf) < 0)
 358                                         error("%s", ebuf);
 359                                 else {
 360                                         for (i = 0; i < devnum-1; i++){
 361                                                 devpointer = devpointer->next;
 362                                                 if (devpointer == NULL)
 363                                                         error("Invalid adapter index");
 364                                         }
 365                                 }
 366                                 device = devpointer->name;
 367                                 break;
 368                         }
 369 #endif /* HAVE_PCAP_FINDALLDEVS */
 370                         device = optarg;
 371                         break;
 372
 373                 case 'l':
 374 #ifdef HAVE_SETLINEBUF
 375                         setlinebuf(stdout);
 376 #else
 377                         setvbuf(stdout, NULL, _IOLBF, 0);
 378 #endif
 379                         break;
 380
 381                 case 'n':
 382                         ++nflag;
 383                         break;
 384
 385                 case 'N':
 386                         ++Nflag;
 387                         break;
 388
 389                 case 'm':
 390 #ifdef LIBSMI
 391                         if (smiLoadModule(optarg) == 0) {
 392                                 error("could not load MIB module %s", optarg);
 393                         }
 394                         sflag = 1;
 395 #else
 396                         (void)fprintf(stderr, "%s: ignoring option `-m %s' ",
 397                                       program_name, optarg);
 398                         (void)fprintf(stderr, "(no libsmi support)\n");
 399 #endif
 400
 401                 case 'O':
 402                         Oflag = 0;
 403                         break;
 404
 405                 case 'p':
 406                         ++pflag;
 407                         break;
 408
 409                 case 'q':
 410                         ++qflag;
 411                         break;
 412
 413                 case 'r':
 414                         RFileName = optarg;
 415                         break;
 416
 417                 case 'R':
 418                         Rflag = 0;
 419                         break;
 420
 421                 case 's': {
 422                         char *end;
 423
 424                         snaplen = strtol(optarg, &end, 0);
 425                         if (optarg == end || *end != '\0'
 426                             || snaplen < 0 || snaplen > 65535)
 427                                 error("invalid snaplen %s", optarg);
 428                         else if (snaplen == 0)
 429                                 snaplen = 65535;
 430                         break;
 431                 }
 432
 433                 case 'S':
 434                         ++Sflag;
 435                         break;
 436
 437                 case 't':
 438                         --tflag;
 439                         break;
 440
 441                 case 'T':
 442                         if (strcasecmp(optarg, "vat") == 0)
 443                                 packettype = PT_VAT;
 444                         else if (strcasecmp(optarg, "wb") == 0)
 445                                 packettype = PT_WB;
 446                         else if (strcasecmp(optarg, "rpc") == 0)
 447                                 packettype = PT_RPC;
 448                         else if (strcasecmp(optarg, "rtp") == 0)
 449                                 packettype = PT_RTP;
 450                         else if (strcasecmp(optarg, "rtcp") == 0)
 451                                 packettype = PT_RTCP;
 452                         else if (strcasecmp(optarg, "snmp") == 0)
 453                                 packettype = PT_SNMP;
 454                         else if (strcasecmp(optarg, "cnfp") == 0)
 455                                 packettype = PT_CNFP;
 456                         else
 457                                 error("unknown packet type `%s'", optarg);
 458                         break;
 459
 460                 case 'u':
 461                         ++uflag;
 462                         break;
 463
 464                 case 'v':
 465                         ++vflag;
 466                         break;
 467
 468                 case 'w':
 469                         WFileName = optarg;
 470                         break;
 471
 472                 case 'x':
 473                         ++xflag;
 474                         break;
 475
 476                 case 'X':
 477                         ++xflag;
 478                         ++Xflag;
 479                         break;
 480
 481 #if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
 482                 case 'Y':
 483                         {
 484                         /* Undocumented flag */
 485 #ifdef HAVE_PCAP_DEBUG
 486                         extern int pcap_debug;
 487                         pcap_debug = 1;
 488 #else
 489                         extern int yydebug;
 490                         yydebug = 1;
 491 #endif
 492                         }
 493                         break;
 494 #endif
 495                 default:
 496                         usage();
 497                         /* NOTREACHED */
 498                 }
 499
 500         if (aflag && nflag)
 501                 error("-a and -n options are incompatible");
 502
 503         if (tflag > 0)
 504                 thiszone = gmt2local(0);
 505
 506         if (RFileName != NULL) {
 507                 /*
 508                  * We don't need network access, so set it back to the user id.
 509                  * Also, this prevents the user from reading anyone's
 510                  * trace file.
 511                  */
 512 #ifndef WIN32
 513                 setuid(getuid());
 514 #endif /* WIN32 */
 515
 516                 pd = pcap_open_offline(RFileName, ebuf);
 517                 if (pd == NULL)
 518                         error("%s", ebuf);
 519                 localnet = 0;
 520                 netmask = 0;
 521                 if (fflag != 0)
 522                         error("-f and -r options are incompatible");
 523         } else {
 524                 if (device == NULL) {
 525                         device = pcap_lookupdev(ebuf);
 526                         if (device == NULL)
 527                                 error("%s", ebuf);
 528                 }
 529 #ifdef WIN32
 530                 PrintCapBegins(program_name,device);
 531 #endif /* WIN32 */
 532                 *ebuf = '\0';
 533                 pd = pcap_open_live(device, snaplen, !pflag, 1000, ebuf);
 534                 if (pd == NULL)
 535                         error("%s", ebuf);
 536                 else if (*ebuf)
 537                         warning("%s", ebuf);
 538 #ifdef WIN32
 539                 if(UserBufferSize != 1000000)
 540                         if(pcap_setbuff(pd, UserBufferSize)==-1){
 541                                 error("%s", pcap_geterr(pd));
 542                         }
 543 #endif /* WIN32 */
 544                 i = pcap_snapshot(pd);
 545                 if (snaplen < i) {
 546                         warning("snaplen raised from %d to %d", snaplen, i);
 547                         snaplen = i;
 548                 }
 549                 if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
 550                         localnet = 0;
 551                         netmask = 0;
 552                         warning("%s", ebuf);
 553                 }
 554                 /*
 555                  * Let user own process after socket has been opened.
 556                  */
 557 #ifndef WIN32
 558                 setuid(getuid());
 559 #endif /* WIN32 */
 560         }
 561         if (infile)
 562                 cmdbuf = read_infile(infile);
 563         else
 564                 cmdbuf = copy_argv(&argv[optind]);
 565
 566         if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
 567                 error("%s", pcap_geterr(pd));
 568         if (dflag) {
 569                 bpf_dump(&fcode, dflag);
 570                 pcap_close(pd);
 571                 exit(0);
 572         }
 573         init_addrtoname(localnet, netmask);
 574
 575         (void)setsignal(SIGTERM, cleanup);
 576         (void)setsignal(SIGINT, cleanup);
 577         /* Cooperate with nohup(1) */
 578 #ifndef WIN32
 579         if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL)
 580                 (void)setsignal(SIGHUP, oldhandler);
 581 #endif /* WIN32 */
 582
 583         if (pcap_setfilter(pd, &fcode) < 0)
 584                 error("%s", pcap_geterr(pd));
 585         if (WFileName) {
 586                 pcap_dumper_t *p = pcap_dump_open(pd, WFileName);
 587                 if (p == NULL)
 588                         error("%s", pcap_geterr(pd));
 589                 if (Cflag != 0) {
 590                         printer = dump_and_trunc;
 591                         dumpinfo.WFileName = WFileName;
 592                         dumpinfo.pd = pd;
 593                         dumpinfo.p = p;
 594                         pcap_userdata = (u_char *)&dumpinfo;
 595                 } else {
 596                         printer = pcap_dump;
 597                         pcap_userdata = (u_char *)p;
 598                 }
 599         } else {
 600                 printer = lookup_printer(pcap_datalink(pd));
 601                 pcap_userdata = 0;
 602 #ifdef SIGINFO
 603                 (void)setsignal(SIGINFO, requestinfo);
 604 #endif
 605         }
 606 #ifndef WIN32
 607         if (RFileName == NULL) {
 608                 (void)fprintf(stderr, "%s: listening on %s\n",
 609                     program_name, device);
 610                 (void)fflush(stderr);
 611         }
 612 #endif /* WIN32 */
 613         if (pcap_loop(pd, cnt, printer, pcap_userdata) < 0) {
 614                 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
 615                     program_name, pcap_geterr(pd));
 616                 cleanup(0);
 617                 pcap_close(pd);
 618                 exit(1);
 619         }
 620         if (RFileName == NULL)
 621                 info(1);
 622         pcap_close(pd);
 623         exit(0);
 624 }
 625
 626 /* make a clean exit on interrupts */
 627 static RETSIGTYPE
 628 cleanup(int signo)
 629 {
 630
 631         /* Can't print the summary if reading from a savefile */
 632         if (pd != NULL && pcap_file(pd) == NULL) {
 633                 (void)fflush(stdout);
 634                 putc('\n', stderr);
 635                 info(1);
 636         }
 637         if (signo)
 638                 exit(0);
 639 }
 640
 641 void
 642 info(register int verbose)
 643 {
 644         struct pcap_stat stat;
 645
 646         if (pcap_stats(pd, &stat) < 0) {
 647                 (void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd));
 648                 return;
 649         }
 650
 651         if (!verbose)
 652                 fprintf(stderr, "%s: ", program_name);
 653
 654         (void)fprintf(stderr, "%d packets received by filter", stat.ps_recv);
 655         if (!verbose)
 656                 fputs(", ", stderr);
 657         else
 658                 putc('\n', stderr);
 659         (void)fprintf(stderr, "%d packets dropped by kernel\n", stat.ps_drop);
 660         infoprint = 0;
 661 }
 662
 663 static void
 664 reverse(char *s)
 665 {
 666         int i, j, c;
 667
 668         for (i = 0, j = strlen(s) - 1; i < j; i++, j--) {
 669                 c = s[i];
 670                 s[i] = s[j];
 671                 s[j] = c;
 672         }
 673 }
 674
 675
 676 static void
 677 swebitoa(unsigned int n, char *s)
 678 {
 679         unsigned int i;
 680
 681         i = 0;
 682         do {
 683                 s[i++] = n % 10 + '0';
 684         } while ((n /= 10) > 0);
 685
 686         s[i] = '\0';
 687         reverse(s);
 688 }
 689
 690 static void
 691 dump_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
 692 {
 693         struct dump_info *info;
 694         static uint cnt = 2;
 695         char *name;
 696
 697         info = (struct dump_info *)user;
 698
 699         /*
 700          * XXX - this won't prevent capture files from getting
 701          * larger than Cflag - the last packet written to the
 702          * file could put it over Cflag.
 703          */
 704         if (ftell((FILE *)info->p) > Cflag) {
 705                 name = (char *) malloc(strlen(info->WFileName) + 4);
 706                 if (name == NULL)
 707                         error("dump_and_trunc: malloc");
 708                 strcpy(name, info->WFileName);
 709                 swebitoa(cnt, name + strlen(info->WFileName));
 710                 cnt++;
 711                 pcap_dump_close(info->p);
 712                 info->p = pcap_dump_open(info->pd, name);
 713                 free(name);
 714                 if (info->p == NULL)
 715                         error("%s", pcap_geterr(pd));
 716         }
 717
 718         pcap_dump((u_char *)info->p, h, sp);
 719 }
 720
 721 /* Like default_print() but data need not be aligned */
 722 void
 723 default_print_unaligned(register const u_char *cp, register u_int length)
 724 {
 725         register u_int i, s;
 726         register int nshorts;
 727
 728         if (Xflag) {
 729                 ascii_print(cp, length);
 730                 return;
 731         }
 732         nshorts = (u_int) length / sizeof(u_short);
 733         i = 0;
 734         while (--nshorts >= 0) {
 735                 if ((i++ % 8) == 0)
 736                         (void)printf("\n\t\t\t");
 737                 s = *cp++;
 738                 (void)printf(" %02x%02x", s, *cp++);
 739         }
 740         if (length & 1) {
 741                 if ((i % 8) == 0)
 742                         (void)printf("\n\t\t\t");
 743                 (void)printf(" %02x", *cp);
 744         }
 745 }
 746
 747 #ifdef WIN32
 748         /*
 749          * XXX - there should really be libpcap calls to get the version
 750          * number as a string (the string would be generated from #defines
 751          * at run time, so that it's not generated from string constants
 752          * in the library, as, on many UNIX systems, those constants would
 753          * be statically linked into the application executable image, and
 754          * would thus reflect the version of libpcap on the system on
 755          * which the application was *linked*, not the system on which it's
 756          * *running*.
 757          *
 758          * That routine should be documented, unlike the "version[]"
 759          * string, so that UNIX vendors providing their own libpcaps
 760          * don't omit it (as a couple of vendors have...).
 761          *
 762          * Packet.dll should perhaps also export a routine to return the
 763          * version number of the Packet.dll code, to supply the
 764          * "Wpcap_version" information on Windows.
 765          */
 766         char WDversion[]="current-cvs.tcpdump.org";
 767         char version[]="current-cvs.tcpdump.org";
 768         char pcap_version[]="current-cvs.tcpdump.org";
 769         char Wpcap_version[]="3.0 alpha";
 770 #endif
 771
 772 /*
 773  * By default, print the packet out in hex.
 774  */
 775 void
 776 default_print(register const u_char *bp, register u_int length)
 777 {
 778         default_print_unaligned(bp, length);
 779 }
 780
 781 #ifdef SIGINFO
 782 RETSIGTYPE requestinfo(int signo _U_)
 783 {
 784         if (infodelay)
 785                 ++infoprint;
 786         else
 787                 info(0);
 788 }
 789 #endif
 790
 791 static void
 792 usage(void)
 793 {
 794         extern char version[];
 795 #if defined(WIN32) || defined(HAVE_PCAP_VERSION)
 796         extern char pcap_version[];
 797 #else
 798         static char pcap_version[] = "unknown";
 799 #endif
 800
 801 #ifdef WIN32
 802         (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
 803         (void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version);
 804 #else
 805         (void)fprintf(stderr, "%s version %s\n", program_name, version);
 806         (void)fprintf(stderr, "libpcap version %s\n", pcap_version);
 807 #endif /* WIN32 */
 808         (void)fprintf(stderr,
 809 #ifdef WIN32
 810 "Usage: %s [-aAdDeflnNOpqRStuvxX] [-B size] [-c count] [ -C file_size ]\n", program_name);
 811 #else /* WIN32 */
 812 #ifdef HAVE_PCAP_FINDALLDEVS
 813 "Usage: %s [-aAdDeflnNOpqRStuvxX] [-c count] [ -C file_size ]\n", program_name);
 814 #else /* HAVE_PCAP_FINDALLDEVS */
 815 "Usage: %s [-aAdeflnNOpqRStuvxX] [-c count] [ -C file_size ]\n", program_name);
 816 #endif /* HAVE_PCAP_FINDALLDEVS */
 817 #endif /* WIN32 */
 818         (void)fprintf(stderr,
 819 "\t\t[ -F file ] [ -i interface ] [ -r file ] [ -s snaplen ]\n");
 820         (void)fprintf(stderr,
 821 "\t\t[ -T type ] [ -w file ] [ -E algo:secret ] [ expression ]\n");
 822         exit(1);
 823 }