1 /* 2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that: (1) source code distributions 7 * retain the above copyright notice and this paragraph in its entirety, (2) 8 * distributions including binary code include the above copyright notice and 9 * this paragraph in its entirety in the documentation or other materials 10 * provided with the distribution, and (3) all advertising materials mentioning 11 * features or use of this software display the following acknowledgement: 12 * ``This product includes software developed by the University of California, 13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 14 * the University nor the names of its contributors may be used to endorse 15 * or promote products derived from this software without specific prior 16 * written permission. 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 20 * 21 * Support for splitting captures into multiple files with a maximum 22 * file size: 23 * 24 * Copyright (c) 2001 25 * Seth Webster <swebster@sst.ll.mit.edu> 26 */ 27 28 #ifndef lint 29 static const char copyright[] _U_ = 30 "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\ 31 The Regents of the University of California. All rights reserved.\n"; 32 #endif 33 34 /* $FreeBSD$ */ 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 "w32_fzs.h" 52 extern int strcasecmp (const char *__s1, const char *__s2); 53 extern int SIZE_BUF; 54 #define off_t long 55 #define uint UINT 56 #endif /* WIN32 */ 57 58 #ifdef USE_LIBSMI 59 #include <smi.h> 60 #endif 61 62 #ifdef HAVE_LIBCRYPTO 63 #include <openssl/crypto.h> 64 #endif 65 66 #ifdef HAVE_GETOPT_LONG 67 #include <getopt.h> 68 #else 69 #include "getopt_long.h" 70 #endif 71 #include <pcap.h> 72 #include <signal.h> 73 #include <stdio.h> 74 #include <stdlib.h> 75 #include <string.h> 76 #include <limits.h> 77 #ifdef __FreeBSD__ 78 #include <sys/capsicum.h> 79 #include <sys/sysctl.h> 80 #endif /* __FreeBSD__ */ 81 #ifdef HAVE_CAPSICUM 82 #include <libcapsicum.h> 83 #include <libcapsicum_dns.h> 84 #include <libcapsicum_service.h> 85 #include <nv.h> 86 #include <sys/capability.h> 87 #include <sys/ioccom.h> 88 #include <net/bpf.h> 89 #include <fcntl.h> 90 #include <libgen.h> 91 #endif /* HAVE_CAPSICUM */ 92 #ifndef WIN32 93 #include <sys/wait.h> 94 #include <sys/resource.h> 95 #include <pwd.h> 96 #include <grp.h> 97 #endif /* WIN32 */ 98 99 /* capabilities convinience library */ 100 #ifdef HAVE_CAP_NG_H 101 #include <cap-ng.h> 102 #endif /* HAVE_CAP_NG_H */ 103 104 #include "netdissect.h" 105 #include "interface.h" 106 #include "addrtoname.h" 107 #include "machdep.h" 108 #include "setsignal.h" 109 #include "gmt2local.h" 110 #include "pcap-missing.h" 111 112 #ifndef PATH_MAX 113 #define PATH_MAX 1024 114 #endif 115 116 #ifdef SIGINFO 117 #define SIGNAL_REQ_INFO SIGINFO 118 #elif SIGUSR1 119 #define SIGNAL_REQ_INFO SIGUSR1 120 #endif 121 122 netdissect_options Gndo; 123 netdissect_options *gndo = &Gndo; 124 125 static int Dflag; /* list available devices and exit */ 126 static int dflag; /* print filter code */ 127 static int Lflag; /* list available data link types and exit */ 128 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE 129 static int Jflag; /* list available time stamp types */ 130 #endif 131 #ifdef HAVE_PCAP_SETDIRECTION 132 int Qflag = -1; /* restrict captured packet by send/receive direction */ 133 #endif 134 static char *zflag = NULL; /* compress each savefile using a specified command (like gzip or bzip2) */ 135 136 static int infodelay; 137 static int infoprint; 138 139 char *program_name; 140 141 #ifdef HAVE_CAPSICUM 142 cap_channel_t *capdns; 143 #endif 144 145 int32_t thiszone; /* seconds offset from gmt to local time */ 146 147 /* Forwards */ 148 static RETSIGTYPE cleanup(int); 149 static RETSIGTYPE child_cleanup(int); 150 static void print_version(void); 151 static void print_usage(void); 152 static void show_dlts_and_exit(const char *device, pcap_t *pd) __attribute__((noreturn)); 153 154 static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *); 155 static void ndo_default_print(netdissect_options *, const u_char *, u_int); 156 static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *); 157 static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *); 158 static void droproot(const char *, const char *); 159 static void ndo_error(netdissect_options *ndo, const char *fmt, ...) 160 __attribute__((noreturn)) 161 #ifdef __ATTRIBUTE___FORMAT_OK 162 __attribute__((format (printf, 2, 3))) 163 #endif /* __ATTRIBUTE___FORMAT_OK */ 164 ; 165 static void ndo_warning(netdissect_options *ndo, const char *fmt, ...) 166 #ifdef __ATTRIBUTE___FORMAT_OK 167 __attribute__((format (printf, 2, 3))) 168 #endif /* __ATTRIBUTE___FORMAT_OK */ 169 ; 170 171 #ifdef SIGNAL_REQ_INFO 172 RETSIGTYPE requestinfo(int); 173 #endif 174 175 #if defined(USE_WIN32_MM_TIMER) 176 #include <MMsystem.h> 177 static UINT timer_id; 178 static void CALLBACK verbose_stats_dump(UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR); 179 #elif defined(HAVE_ALARM) 180 static void verbose_stats_dump(int sig); 181 #endif 182 183 static void info(int); 184 static u_int packets_captured; 185 186 struct printer { 187 if_printer f; 188 int type; 189 }; 190 191 192 struct ndo_printer { 193 if_ndo_printer f; 194 int type; 195 }; 196 197 198 static const struct printer printers[] = { 199 { NULL, 0 }, 200 }; 201 202 static const struct ndo_printer ndo_printers[] = { 203 { ether_if_print, DLT_EN10MB }, 204 #ifdef DLT_IPNET 205 { ipnet_if_print, DLT_IPNET }, 206 #endif 207 #ifdef DLT_IEEE802_15_4 208 { ieee802_15_4_if_print, DLT_IEEE802_15_4 }, 209 #endif 210 #ifdef DLT_IEEE802_15_4_NOFCS 211 { ieee802_15_4_if_print, DLT_IEEE802_15_4_NOFCS }, 212 #endif 213 #ifdef DLT_PPI 214 { ppi_if_print, DLT_PPI }, 215 #endif 216 #ifdef DLT_NETANALYZER 217 { netanalyzer_if_print, DLT_NETANALYZER }, 218 #endif 219 #ifdef DLT_NETANALYZER_TRANSPARENT 220 { netanalyzer_transparent_if_print, DLT_NETANALYZER_TRANSPARENT }, 221 #endif 222 #if defined(DLT_NFLOG) && defined(HAVE_PCAP_NFLOG_H) 223 { nflog_if_print, DLT_NFLOG}, 224 #endif 225 #ifdef DLT_CIP 226 { cip_if_print, DLT_CIP }, 227 #endif 228 #ifdef DLT_ATM_CLIP 229 { cip_if_print, DLT_ATM_CLIP }, 230 #endif 231 #ifdef DLT_IP_OVER_FC 232 { ipfc_if_print, DLT_IP_OVER_FC }, 233 #endif 234 { null_if_print, DLT_NULL }, 235 #ifdef DLT_LOOP 236 { null_if_print, DLT_LOOP }, 237 #endif 238 #ifdef DLT_APPLE_IP_OVER_IEEE1394 239 { ap1394_if_print, DLT_APPLE_IP_OVER_IEEE1394 }, 240 #endif 241 #if defined(DLT_BLUETOOTH_HCI_H4_WITH_PHDR) && defined(HAVE_PCAP_BLUETOOTH_H) 242 { bt_if_print, DLT_BLUETOOTH_HCI_H4_WITH_PHDR}, 243 #endif 244 #ifdef DLT_LANE8023 245 { lane_if_print, DLT_LANE8023 }, 246 #endif 247 { arcnet_if_print, DLT_ARCNET }, 248 #ifdef DLT_ARCNET_LINUX 249 { arcnet_linux_if_print, DLT_ARCNET_LINUX }, 250 #endif 251 { raw_if_print, DLT_RAW }, 252 #ifdef DLT_IPV4 253 { raw_if_print, DLT_IPV4 }, 254 #endif 255 #ifdef DLT_IPV6 256 { raw_if_print, DLT_IPV6 }, 257 #endif 258 #ifdef HAVE_PCAP_USB_H 259 #ifdef DLT_USB_LINUX 260 { usb_linux_48_byte_print, DLT_USB_LINUX}, 261 #endif /* DLT_USB_LINUX */ 262 #ifdef DLT_USB_LINUX_MMAPPED 263 { usb_linux_64_byte_print, DLT_USB_LINUX_MMAPPED}, 264 #endif /* DLT_USB_LINUX_MMAPPED */ 265 #endif /* HAVE_PCAP_USB_H */ 266 #ifdef DLT_SYMANTEC_FIREWALL 267 { symantec_if_print, DLT_SYMANTEC_FIREWALL }, 268 #endif 269 #ifdef DLT_C_HDLC 270 { chdlc_if_print, DLT_C_HDLC }, 271 #endif 272 #ifdef DLT_HDLC 273 { chdlc_if_print, DLT_HDLC }, 274 #endif 275 #ifdef DLT_PPP_ETHER 276 { pppoe_if_print, DLT_PPP_ETHER }, 277 #endif 278 #if defined(DLT_PFLOG) && defined(HAVE_NET_PFVAR_H) 279 { pflog_if_print, DLT_PFLOG }, 280 #endif 281 { token_if_print, DLT_IEEE802 }, 282 { fddi_if_print, DLT_FDDI }, 283 #ifdef DLT_LINUX_SLL 284 { sll_if_print, DLT_LINUX_SLL }, 285 #endif 286 #ifdef DLT_FR 287 { fr_if_print, DLT_FR }, 288 #endif 289 #ifdef DLT_FRELAY 290 { fr_if_print, DLT_FRELAY }, 291 #endif 292 #ifdef DLT_MFR 293 { mfr_if_print, DLT_MFR }, 294 #endif 295 { atm_if_print, DLT_ATM_RFC1483 }, 296 #ifdef DLT_SUNATM 297 { sunatm_if_print, DLT_SUNATM }, 298 #endif 299 #ifdef DLT_ENC 300 { enc_if_print, DLT_ENC }, 301 #endif 302 { sl_if_print, DLT_SLIP }, 303 #ifdef DLT_SLIP_BSDOS 304 { sl_bsdos_if_print, DLT_SLIP_BSDOS }, 305 #endif 306 #ifdef DLT_LTALK 307 { ltalk_if_print, DLT_LTALK }, 308 #endif 309 #ifdef DLT_JUNIPER_ATM1 310 { juniper_atm1_print, DLT_JUNIPER_ATM1 }, 311 #endif 312 #ifdef DLT_JUNIPER_ATM2 313 { juniper_atm2_print, DLT_JUNIPER_ATM2 }, 314 #endif 315 #ifdef DLT_JUNIPER_MFR 316 { juniper_mfr_print, DLT_JUNIPER_MFR }, 317 #endif 318 #ifdef DLT_JUNIPER_MLFR 319 { juniper_mlfr_print, DLT_JUNIPER_MLFR }, 320 #endif 321 #ifdef DLT_JUNIPER_MLPPP 322 { juniper_mlppp_print, DLT_JUNIPER_MLPPP }, 323 #endif 324 #ifdef DLT_JUNIPER_PPPOE 325 { juniper_pppoe_print, DLT_JUNIPER_PPPOE }, 326 #endif 327 #ifdef DLT_JUNIPER_PPPOE_ATM 328 { juniper_pppoe_atm_print, DLT_JUNIPER_PPPOE_ATM }, 329 #endif 330 #ifdef DLT_JUNIPER_GGSN 331 { juniper_ggsn_print, DLT_JUNIPER_GGSN }, 332 #endif 333 #ifdef DLT_JUNIPER_ES 334 { juniper_es_print, DLT_JUNIPER_ES }, 335 #endif 336 #ifdef DLT_JUNIPER_MONITOR 337 { juniper_monitor_print, DLT_JUNIPER_MONITOR }, 338 #endif 339 #ifdef DLT_JUNIPER_SERVICES 340 { juniper_services_print, DLT_JUNIPER_SERVICES }, 341 #endif 342 #ifdef DLT_JUNIPER_ETHER 343 { juniper_ether_print, DLT_JUNIPER_ETHER }, 344 #endif 345 #ifdef DLT_JUNIPER_PPP 346 { juniper_ppp_print, DLT_JUNIPER_PPP }, 347 #endif 348 #ifdef DLT_JUNIPER_FRELAY 349 { juniper_frelay_print, DLT_JUNIPER_FRELAY }, 350 #endif 351 #ifdef DLT_JUNIPER_CHDLC 352 { juniper_chdlc_print, DLT_JUNIPER_CHDLC }, 353 #endif 354 #ifdef DLT_PKTAP 355 { pktap_if_print, DLT_PKTAP }, 356 #endif 357 #ifdef DLT_IEEE802_11_RADIO 358 { ieee802_11_radio_if_print, DLT_IEEE802_11_RADIO }, 359 #endif 360 #ifdef DLT_IEEE802_11 361 { ieee802_11_if_print, DLT_IEEE802_11}, 362 #endif 363 #ifdef DLT_IEEE802_11_RADIO_AVS 364 { ieee802_11_radio_avs_if_print, DLT_IEEE802_11_RADIO_AVS }, 365 #endif 366 #ifdef DLT_PRISM_HEADER 367 { prism_if_print, DLT_PRISM_HEADER }, 368 #endif 369 { ppp_if_print, DLT_PPP }, 370 #ifdef DLT_PPP_WITHDIRECTION 371 { ppp_if_print, DLT_PPP_WITHDIRECTION }, 372 #endif 373 #ifdef DLT_PPP_BSDOS 374 { ppp_bsdos_if_print, DLT_PPP_BSDOS }, 375 #endif 376 #ifdef DLT_PPP_SERIAL 377 { ppp_hdlc_if_print, DLT_PPP_SERIAL }, 378 #endif 379 { NULL, 0 }, 380 }; 381 382 static const struct tok status_flags[] = { 383 #ifdef PCAP_IF_UP 384 { PCAP_IF_UP, "Up" }, 385 #endif 386 #ifdef PCAP_IF_RUNNING 387 { PCAP_IF_RUNNING, "Running" }, 388 #endif 389 { PCAP_IF_LOOPBACK, "Loopback" }, 390 { 0, NULL } 391 }; 392 393 if_printer 394 lookup_printer(int type) 395 { 396 const struct printer *p; 397 398 for (p = printers; p->f; ++p) 399 if (type == p->type) 400 return p->f; 401 402 return NULL; 403 /* NOTREACHED */ 404 } 405 406 if_ndo_printer 407 lookup_ndo_printer(int type) 408 { 409 const struct ndo_printer *p; 410 411 for (p = ndo_printers; p->f; ++p) 412 if (type == p->type) 413 return p->f; 414 415 #if defined(DLT_USER2) && defined(DLT_PKTAP) 416 /* 417 * Apple incorrectly chose to use DLT_USER2 for their PKTAP 418 * header. 419 * 420 * We map DLT_PKTAP, whether it's DLT_USER2 as it is on Darwin- 421 * based OSes or the same value as LINKTYPE_PKTAP as it is on 422 * other OSes, to LINKTYPE_PKTAP, so files written with 423 * this version of libpcap for a DLT_PKTAP capture have a link- 424 * layer header type of LINKTYPE_PKTAP. 425 * 426 * However, files written on OS X Mavericks for a DLT_PKTAP 427 * capture have a link-layer header type of LINKTYPE_USER2. 428 * If we don't have a printer for DLT_USER2, and type is 429 * DLT_USER2, we look up the printer for DLT_PKTAP and use 430 * that. 431 */ 432 if (type == DLT_USER2) { 433 for (p = ndo_printers; p->f; ++p) 434 if (DLT_PKTAP == p->type) 435 return p->f; 436 } 437 #endif 438 439 return NULL; 440 /* NOTREACHED */ 441 } 442 443 static pcap_t *pd; 444 445 static int supports_monitor_mode; 446 447 extern int optind; 448 extern int opterr; 449 extern char *optarg; 450 451 struct print_info { 452 netdissect_options *ndo; 453 union { 454 if_printer printer; 455 if_ndo_printer ndo_printer; 456 } p; 457 int ndo_type; 458 }; 459 460 struct dump_info { 461 char *WFileName; 462 char *CurrentFileName; 463 pcap_t *pd; 464 pcap_dumper_t *p; 465 #ifdef HAVE_CAPSICUM 466 int dirfd; 467 #endif 468 }; 469 470 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE 471 static void 472 show_tstamp_types_and_exit(const char *device, pcap_t *pd) 473 { 474 int n_tstamp_types; 475 int *tstamp_types = 0; 476 const char *tstamp_type_name; 477 int i; 478 479 n_tstamp_types = pcap_list_tstamp_types(pd, &tstamp_types); 480 if (n_tstamp_types < 0) 481 error("%s", pcap_geterr(pd)); 482 483 if (n_tstamp_types == 0) { 484 fprintf(stderr, "Time stamp type cannot be set for %s\n", 485 device); 486 exit(0); 487 } 488 fprintf(stderr, "Time stamp types for %s (use option -j to set):\n", 489 device); 490 for (i = 0; i < n_tstamp_types; i++) { 491 tstamp_type_name = pcap_tstamp_type_val_to_name(tstamp_types[i]); 492 if (tstamp_type_name != NULL) { 493 (void) fprintf(stderr, " %s (%s)\n", tstamp_type_name, 494 pcap_tstamp_type_val_to_description(tstamp_types[i])); 495 } else { 496 (void) fprintf(stderr, " %d\n", tstamp_types[i]); 497 } 498 } 499 pcap_free_tstamp_types(tstamp_types); 500 exit(0); 501 } 502 #endif 503 504 static void 505 show_dlts_and_exit(const char *device, pcap_t *pd) 506 { 507 int n_dlts; 508 int *dlts = 0; 509 const char *dlt_name; 510 511 n_dlts = pcap_list_datalinks(pd, &dlts); 512 if (n_dlts < 0) 513 error("%s", pcap_geterr(pd)); 514 else if (n_dlts == 0 || !dlts) 515 error("No data link types."); 516 517 /* 518 * If the interface is known to support monitor mode, indicate 519 * whether these are the data link types available when not in 520 * monitor mode, if -I wasn't specified, or when in monitor mode, 521 * when -I was specified (the link-layer types available in 522 * monitor mode might be different from the ones available when 523 * not in monitor mode). 524 */ 525 if (supports_monitor_mode) 526 (void) fprintf(stderr, "Data link types for %s %s (use option -y to set):\n", 527 device, 528 Iflag ? "when in monitor mode" : "when not in monitor mode"); 529 else 530 (void) fprintf(stderr, "Data link types for %s (use option -y to set):\n", 531 device); 532 533 while (--n_dlts >= 0) { 534 dlt_name = pcap_datalink_val_to_name(dlts[n_dlts]); 535 if (dlt_name != NULL) { 536 (void) fprintf(stderr, " %s (%s)", dlt_name, 537 pcap_datalink_val_to_description(dlts[n_dlts])); 538 539 /* 540 * OK, does tcpdump handle that type? 541 */ 542 if (lookup_printer(dlts[n_dlts]) == NULL 543 && lookup_ndo_printer(dlts[n_dlts]) == NULL) 544 (void) fprintf(stderr, " (printing not supported)"); 545 fprintf(stderr, "\n"); 546 } else { 547 (void) fprintf(stderr, " DLT %d (printing not supported)\n", 548 dlts[n_dlts]); 549 } 550 } 551 #ifdef HAVE_PCAP_FREE_DATALINKS 552 pcap_free_datalinks(dlts); 553 #endif 554 exit(0); 555 } 556 557 #ifdef HAVE_PCAP_FINDALLDEVS 558 static void 559 show_devices_and_exit (void) 560 { 561 pcap_if_t *devpointer; 562 char ebuf[PCAP_ERRBUF_SIZE]; 563 int i; 564 565 if (pcap_findalldevs(&devpointer, ebuf) < 0) 566 error("%s", ebuf); 567 else { 568 for (i = 0; devpointer != NULL; i++) { 569 printf("%d.%s", i+1, devpointer->name); 570 if (devpointer->description != NULL) 571 printf(" (%s)", devpointer->description); 572 if (devpointer->flags != 0) 573 printf(" [%s]", bittok2str(status_flags, "none", devpointer->flags)); 574 printf("\n"); 575 devpointer = devpointer->next; 576 } 577 } 578 exit(0); 579 } 580 #endif /* HAVE_PCAP_FINDALLDEVS */ 581 582 /* 583 * Short options. 584 * 585 * Note that there we use all letters for short options except for g, k, 586 * o, and P, and those are used by other versions of tcpdump, and we should 587 * only use them for the same purposes that the other versions of tcpdump 588 * use them: 589 * 590 * OS X tcpdump uses -g to force non--v output for IP to be on one 591 * line, making it more "g"repable; 592 * 593 * OS X tcpdump uses -k tospecify that packet comments in pcap-ng files 594 * should be printed; 595 * 596 * OpenBSD tcpdump uses -o to indicate that OS fingerprinting should be done 597 * for hosts sending TCP SYN packets; 598 * 599 * OS X tcpdump uses -P to indicate that -w should write pcap-ng rather 600 * than pcap files. 601 */ 602 603 /* 604 * Set up flags that might or might not be supported depending on the 605 * version of libpcap we're using. 606 */ 607 #if defined(HAVE_PCAP_CREATE) || defined(WIN32) 608 #define B_FLAG "B:" 609 #define B_FLAG_USAGE " [ -B size ]" 610 #else /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */ 611 #define B_FLAG 612 #define B_FLAG_USAGE 613 #endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */ 614 615 #ifdef HAVE_PCAP_CREATE 616 #define I_FLAG "I" 617 #else /* HAVE_PCAP_CREATE */ 618 #define I_FLAG 619 #endif /* HAVE_PCAP_CREATE */ 620 621 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE 622 #define j_FLAG "j:" 623 #define j_FLAG_USAGE " [ -j tstamptype ]" 624 #define J_FLAG "J" 625 #else /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */ 626 #define j_FLAG 627 #define j_FLAG_USAGE 628 #define J_FLAG 629 #endif /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */ 630 631 #ifdef HAVE_PCAP_FINDALLDEVS 632 #ifndef HAVE_PCAP_IF_T 633 #undef HAVE_PCAP_FINDALLDEVS 634 #endif 635 #endif 636 637 #ifdef HAVE_PCAP_FINDALLDEVS 638 #define D_FLAG "D" 639 #else 640 #define D_FLAG 641 #endif 642 643 #ifdef HAVE_PCAP_DUMP_FLUSH 644 #define U_FLAG "U" 645 #else 646 #define U_FLAG 647 #endif 648 649 #ifdef HAVE_PCAP_SETDIRECTION 650 #define Q_FLAG "Q:" 651 #else 652 #define Q_FLAG 653 #endif 654 655 /* 656 * Long options. 657 * 658 * We do not currently have long options corresponding to all short 659 * options; we should probably pick appropriate option names for them. 660 * 661 * However, the short options where the number of times the option is 662 * specified matters, such as -v and -d and -t, should probably not 663 * just map to a long option, as saying 664 * 665 * tcpdump --verbose --verbose 666 * 667 * doesn't make sense; it should be --verbosity={N} or something such 668 * as that. 669 * 670 * For long options with no corresponding short options, we define values 671 * outside the range of ASCII graphic characters, make that the last 672 * component of the entry for the long option, and have a case for that 673 * option in the switch statement. 674 */ 675 #define OPTION_VERSION 128 676 #define OPTION_TSTAMP_PRECISION 129 677 678 static const struct option longopts[] = { 679 #if defined(HAVE_PCAP_CREATE) || defined(WIN32) 680 { "buffer-size", required_argument, NULL, 'B' }, 681 #endif 682 { "list-interfaces", no_argument, NULL, 'D' }, 683 { "help", no_argument, NULL, 'h' }, 684 { "interface", required_argument, NULL, 'i' }, 685 #ifdef HAVE_PCAP_CREATE 686 { "monitor-mode", no_argument, NULL, 'I' }, 687 #endif 688 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE 689 { "time-stamp-type", required_argument, NULL, 'j' }, 690 { "list-time-stamp-types", no_argument, NULL, 'J' }, 691 #endif 692 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION 693 { "time-stamp-precision", required_argument, NULL, OPTION_TSTAMP_PRECISION}, 694 #endif 695 { "dont-verify-checksums", no_argument, NULL, 'K' }, 696 { "list-data-link-types", no_argument, NULL, 'L' }, 697 { "no-optimize", no_argument, NULL, 'O' }, 698 { "no-promiscuous-mode", no_argument, NULL, 'p' }, 699 #ifdef HAVE_PCAP_SETDIRECTION 700 { "direction", required_argument, NULL, 'Q' }, 701 #endif 702 { "snapshot-length", required_argument, NULL, 's' }, 703 { "absolute-tcp-sequence-numbers", no_argument, NULL, 'S' }, 704 #ifdef HAVE_PCAP_DUMP_FLUSH 705 { "packet-buffered", no_argument, NULL, 'U' }, 706 #endif 707 { "linktype", required_argument, NULL, 'y' }, 708 #if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG) 709 { "debug-filter-parser", no_argument, NULL, 'Y' }, 710 #endif 711 { "relinquish-privileges", required_argument, NULL, 'Z' }, 712 { "number", no_argument, NULL, '#' }, 713 { "version", no_argument, NULL, OPTION_VERSION }, 714 { NULL, 0, NULL, 0 } 715 }; 716 717 #ifndef WIN32 718 /* Drop root privileges and chroot if necessary */ 719 static void 720 droproot(const char *username, const char *chroot_dir) 721 { 722 struct passwd *pw = NULL; 723 724 if (chroot_dir && !username) { 725 fprintf(stderr, "tcpdump: Chroot without dropping root is insecure\n"); 726 exit(1); 727 } 728 729 pw = getpwnam(username); 730 if (pw) { 731 if (chroot_dir) { 732 if (chroot(chroot_dir) != 0 || chdir ("/") != 0) { 733 fprintf(stderr, "tcpdump: Couldn't chroot/chdir to '%.64s': %s\n", 734 chroot_dir, pcap_strerror(errno)); 735 exit(1); 736 } 737 } 738 #ifdef HAVE_CAP_NG_H 739 int ret = capng_change_id(pw->pw_uid, pw->pw_gid, CAPNG_NO_FLAG); 740 if (ret < 0) { 741 fprintf(stderr, "error : ret %d\n", ret); 742 } 743 else { 744 printf("dropped privs to %s\n", username); 745 } 746 /* We don't need CAP_SETUID and CAP_SETGID */ 747 capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_SETUID); 748 capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_SETUID); 749 capng_update(CAPNG_DROP, CAPNG_PERMITTED, CAP_SETUID); 750 capng_update(CAPNG_DROP, CAPNG_PERMITTED, CAP_SETUID); 751 capng_apply(CAPNG_SELECT_BOTH); 752 753 #else 754 if (initgroups(pw->pw_name, pw->pw_gid) != 0 || 755 setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) { 756 fprintf(stderr, "tcpdump: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n", 757 username, 758 (unsigned long)pw->pw_uid, 759 (unsigned long)pw->pw_gid, 760 pcap_strerror(errno)); 761 exit(1); 762 } 763 else { 764 printf("dropped privs to %s\n", username); 765 } 766 #endif /* HAVE_CAP_NG_H */ 767 } 768 else { 769 fprintf(stderr, "tcpdump: Couldn't find user '%.32s'\n", 770 username); 771 exit(1); 772 } 773 } 774 #endif /* WIN32 */ 775 776 static int 777 getWflagChars(int x) 778 { 779 int c = 0; 780 781 x -= 1; 782 while (x > 0) { 783 c += 1; 784 x /= 10; 785 } 786 787 return c; 788 } 789 790 791 static void 792 MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars) 793 { 794 char *filename = malloc(PATH_MAX + 1); 795 if (filename == NULL) 796 error("Makefilename: malloc"); 797 798 /* Process with strftime if Gflag is set. */ 799 if (Gflag != 0) { 800 struct tm *local_tm; 801 802 /* Convert Gflag_time to a usable format */ 803 if ((local_tm = localtime(&Gflag_time)) == NULL) { 804 error("MakeTimedFilename: localtime"); 805 } 806 807 /* There's no good way to detect an error in strftime since a return 808 * value of 0 isn't necessarily failure. 809 */ 810 strftime(filename, PATH_MAX, orig_name, local_tm); 811 } else { 812 strncpy(filename, orig_name, PATH_MAX); 813 } 814 815 if (cnt == 0 && max_chars == 0) 816 strncpy(buffer, filename, PATH_MAX + 1); 817 else 818 if (snprintf(buffer, PATH_MAX + 1, "%s%0*d", filename, max_chars, cnt) > PATH_MAX) 819 /* Report an error if the filename is too large */ 820 error("too many output files or filename is too long (> %d)", PATH_MAX); 821 free(filename); 822 } 823 824 static int tcpdump_printf(netdissect_options *ndo _U_, 825 const char *fmt, ...) 826 { 827 828 va_list args; 829 int ret; 830 831 va_start(args, fmt); 832 ret=vfprintf(stdout, fmt, args); 833 va_end(args); 834 835 return ret; 836 } 837 838 static struct print_info 839 get_print_info(int type) 840 { 841 struct print_info printinfo; 842 843 printinfo.ndo_type = 1; 844 printinfo.ndo = gndo; 845 printinfo.p.ndo_printer = lookup_ndo_printer(type); 846 if (printinfo.p.ndo_printer == NULL) { 847 printinfo.p.printer = lookup_printer(type); 848 printinfo.ndo_type = 0; 849 if (printinfo.p.printer == NULL) { 850 gndo->ndo_dltname = pcap_datalink_val_to_name(type); 851 if (gndo->ndo_dltname != NULL) 852 error("packet printing is not supported for link type %s: use -w", 853 gndo->ndo_dltname); 854 else 855 error("packet printing is not supported for link type %d: use -w", type); 856 } 857 } 858 return (printinfo); 859 } 860 861 static char * 862 get_next_file(FILE *VFile, char *ptr) 863 { 864 char *ret; 865 866 ret = fgets(ptr, PATH_MAX, VFile); 867 if (!ret) 868 return NULL; 869 870 if (ptr[strlen(ptr) - 1] == '\n') 871 ptr[strlen(ptr) - 1] = '\0'; 872 873 return ret; 874 } 875 876 #ifdef HAVE_CAPSICUM 877 static cap_channel_t * 878 capdns_setup(void) 879 { 880 cap_channel_t *capcas, *capdnsloc; 881 const char *types[1]; 882 int families[2]; 883 884 capcas = cap_init(); 885 if (capcas == NULL) { 886 warning("unable to contact casperd"); 887 return (NULL); 888 } 889 capdnsloc = cap_service_open(capcas, "system.dns"); 890 /* Casper capability no longer needed. */ 891 cap_close(capcas); 892 if (capdnsloc == NULL) 893 error("unable to open system.dns service"); 894 /* Limit system.dns to reverse DNS lookups. */ 895 types[0] = "ADDR"; 896 if (cap_dns_type_limit(capdnsloc, types, 1) < 0) 897 error("unable to limit access to system.dns service"); 898 families[0] = AF_INET; 899 families[1] = AF_INET6; 900 if (cap_dns_family_limit(capdnsloc, families, 2) < 0) 901 error("unable to limit access to system.dns service"); 902 903 return (capdnsloc); 904 } 905 #endif /* HAVE_CAPSICUM */ 906 907 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION 908 static int 909 tstamp_precision_from_string(const char *precision) 910 { 911 if (strncmp(precision, "nano", strlen("nano")) == 0) 912 return PCAP_TSTAMP_PRECISION_NANO; 913 914 if (strncmp(precision, "micro", strlen("micro")) == 0) 915 return PCAP_TSTAMP_PRECISION_MICRO; 916 917 return -EINVAL; 918 } 919 920 static const char * 921 tstamp_precision_to_string(int precision) 922 { 923 switch (precision) { 924 925 case PCAP_TSTAMP_PRECISION_MICRO: 926 return "micro"; 927 928 case PCAP_TSTAMP_PRECISION_NANO: 929 return "nano"; 930 931 default: 932 return "unknown"; 933 } 934 } 935 #endif 936 937 int 938 main(int argc, char **argv) 939 { 940 register int cnt, op, i; 941 bpf_u_int32 localnet =0 , netmask = 0; 942 register char *cp, *infile, *cmdbuf, *device, *RFileName, *VFileName, *WFileName; 943 pcap_handler callback; 944 int type; 945 int dlt; 946 int new_dlt; 947 const char *dlt_name; 948 struct bpf_program fcode; 949 #ifndef WIN32 950 RETSIGTYPE (*oldhandler)(int); 951 #endif 952 struct print_info printinfo; 953 struct dump_info dumpinfo; 954 u_char *pcap_userdata; 955 char ebuf[PCAP_ERRBUF_SIZE]; 956 char VFileLine[PATH_MAX + 1]; 957 char *username = NULL; 958 char *chroot_dir = NULL; 959 char *ret = NULL; 960 char *end; 961 #ifdef HAVE_PCAP_FINDALLDEVS 962 pcap_if_t *devpointer; 963 int devnum; 964 #endif 965 int status; 966 FILE *VFile; 967 #ifdef HAVE_CAPSICUM 968 cap_rights_t rights; 969 #endif /* HAVE_CAPSICUM */ 970 int cansandbox; 971 972 #ifdef WIN32 973 if(wsockinit() != 0) return 1; 974 #endif /* WIN32 */ 975 976 jflag=-1; /* not set */ 977 gndo->ndo_Oflag=1; 978 gndo->ndo_Rflag=1; 979 gndo->ndo_dlt=-1; 980 gndo->ndo_default_print=ndo_default_print; 981 gndo->ndo_printf=tcpdump_printf; 982 gndo->ndo_error=ndo_error; 983 gndo->ndo_warning=ndo_warning; 984 gndo->ndo_snaplen = DEFAULT_SNAPLEN; 985 986 cnt = -1; 987 device = NULL; 988 infile = NULL; 989 RFileName = NULL; 990 VFileName = NULL; 991 VFile = NULL; 992 WFileName = NULL; 993 dlt = -1; 994 if ((cp = strrchr(argv[0], '/')) != NULL) 995 program_name = cp + 1; 996 else 997 program_name = argv[0]; 998 999 if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0) 1000 error("%s", ebuf); 1001 1002 #ifdef USE_LIBSMI 1003 smiInit("tcpdump"); 1004 #endif 1005 1006 while ( 1007 (op = getopt_long(argc, argv, "aAb" B_FLAG "c:C:d" D_FLAG "eE:fF:G:hHi:" I_FLAG j_FLAG J_FLAG "KlLm:M:nNOpq" Q_FLAG "r:Rs:StT:u" U_FLAG "vV:w:W:xXy:Yz:Z:#", longopts, NULL)) != -1) 1008 switch (op) { 1009 1010 case 'a': 1011 /* compatibility for old -a */ 1012 break; 1013 1014 case 'A': 1015 ++Aflag; 1016 break; 1017 1018 case 'b': 1019 ++bflag; 1020 break; 1021 1022 #if defined(HAVE_PCAP_CREATE) || defined(WIN32) 1023 case 'B': 1024 Bflag = atoi(optarg)*1024; 1025 if (Bflag <= 0) 1026 error("invalid packet buffer size %s", optarg); 1027 break; 1028 #endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */ 1029 1030 case 'c': 1031 cnt = atoi(optarg); 1032 if (cnt <= 0) 1033 error("invalid packet count %s", optarg); 1034 break; 1035 1036 case 'C': 1037 Cflag = atoi(optarg) * 1000000; 1038 if (Cflag < 0) 1039 error("invalid file size %s", optarg); 1040 break; 1041 1042 case 'd': 1043 ++dflag; 1044 break; 1045 1046 case 'D': 1047 Dflag++; 1048 break; 1049 1050 case 'L': 1051 Lflag++; 1052 break; 1053 1054 case 'e': 1055 ++eflag; 1056 break; 1057 1058 case 'E': 1059 #ifndef HAVE_LIBCRYPTO 1060 warning("crypto code not compiled in"); 1061 #endif 1062 gndo->ndo_espsecret = optarg; 1063 break; 1064 1065 case 'f': 1066 ++fflag; 1067 break; 1068 1069 case 'F': 1070 infile = optarg; 1071 break; 1072 1073 case 'G': 1074 Gflag = atoi(optarg); 1075 if (Gflag < 0) 1076 error("invalid number of seconds %s", optarg); 1077 1078 /* We will create one file initially. */ 1079 Gflag_count = 0; 1080 1081 /* Grab the current time for rotation use. */ 1082 if ((Gflag_time = time(NULL)) == (time_t)-1) { 1083 error("main: can't get current time: %s", 1084 pcap_strerror(errno)); 1085 } 1086 break; 1087 1088 case 'h': 1089 print_usage(); 1090 exit(0); 1091 break; 1092 1093 case 'H': 1094 ++Hflag; 1095 break; 1096 1097 case 'i': 1098 if (optarg[0] == '0' && optarg[1] == 0) 1099 error("Invalid adapter index"); 1100 1101 #ifdef HAVE_PCAP_FINDALLDEVS 1102 /* 1103 * If the argument is a number, treat it as 1104 * an index into the list of adapters, as 1105 * printed by "tcpdump -D". 1106 * 1107 * This should be OK on UNIX systems, as interfaces 1108 * shouldn't have names that begin with digits. 1109 * It can be useful on Windows, where more than 1110 * one interface can have the same name. 1111 */ 1112 devnum = strtol(optarg, &end, 10); 1113 if (optarg != end && *end == '\0') { 1114 if (devnum < 0) 1115 error("Invalid adapter index"); 1116 1117 if (pcap_findalldevs(&devpointer, ebuf) < 0) 1118 error("%s", ebuf); 1119 else { 1120 /* 1121 * Look for the devnum-th entry 1122 * in the list of devices 1123 * (1-based). 1124 */ 1125 for (i = 0; 1126 i < devnum-1 && devpointer != NULL; 1127 i++, devpointer = devpointer->next) 1128 ; 1129 if (devpointer == NULL) 1130 error("Invalid adapter index"); 1131 } 1132 device = devpointer->name; 1133 break; 1134 } 1135 #endif /* HAVE_PCAP_FINDALLDEVS */ 1136 device = optarg; 1137 break; 1138 1139 #ifdef HAVE_PCAP_CREATE 1140 case 'I': 1141 ++Iflag; 1142 break; 1143 #endif /* HAVE_PCAP_CREATE */ 1144 1145 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE 1146 case 'j': 1147 jflag = pcap_tstamp_type_name_to_val(optarg); 1148 if (jflag < 0) 1149 error("invalid time stamp type %s", optarg); 1150 break; 1151 1152 case 'J': 1153 Jflag++; 1154 break; 1155 #endif 1156 1157 case 'l': 1158 #ifdef WIN32 1159 /* 1160 * _IOLBF is the same as _IOFBF in Microsoft's C 1161 * libraries; the only alternative they offer 1162 * is _IONBF. 1163 * 1164 * XXX - this should really be checking for MSVC++, 1165 * not WIN32, if, for example, MinGW has its own 1166 * C library that is more UNIX-compatible. 1167 */ 1168 setvbuf(stdout, NULL, _IONBF, 0); 1169 #else /* WIN32 */ 1170 #ifdef HAVE_SETLINEBUF 1171 setlinebuf(stdout); 1172 #else 1173 setvbuf(stdout, NULL, _IOLBF, 0); 1174 #endif 1175 #endif /* WIN32 */ 1176 break; 1177 1178 case 'K': 1179 ++Kflag; 1180 break; 1181 1182 case 'm': 1183 #ifdef USE_LIBSMI 1184 if (smiLoadModule(optarg) == 0) { 1185 error("could not load MIB module %s", optarg); 1186 } 1187 sflag = 1; 1188 #else 1189 (void)fprintf(stderr, "%s: ignoring option `-m %s' ", 1190 program_name, optarg); 1191 (void)fprintf(stderr, "(no libsmi support)\n"); 1192 #endif 1193 break; 1194 1195 case 'M': 1196 /* TCP-MD5 shared secret */ 1197 #ifndef HAVE_LIBCRYPTO 1198 warning("crypto code not compiled in"); 1199 #endif 1200 sigsecret = optarg; 1201 break; 1202 1203 case 'n': 1204 ++nflag; 1205 break; 1206 1207 case 'N': 1208 ++Nflag; 1209 break; 1210 1211 case 'O': 1212 Oflag = 0; 1213 break; 1214 1215 case 'p': 1216 ++pflag; 1217 break; 1218 1219 case 'q': 1220 ++qflag; 1221 ++suppress_default_print; 1222 break; 1223 1224 #ifdef HAVE_PCAP_SETDIRECTION 1225 case 'Q': 1226 if (strcasecmp(optarg, "in") == 0) 1227 Qflag = PCAP_D_IN; 1228 else if (strcasecmp(optarg, "out") == 0) 1229 Qflag = PCAP_D_OUT; 1230 else if (strcasecmp(optarg, "inout") == 0) 1231 Qflag = PCAP_D_INOUT; 1232 else 1233 error("unknown capture direction `%s'", optarg); 1234 break; 1235 #endif /* HAVE_PCAP_SETDIRECTION */ 1236 1237 case 'r': 1238 RFileName = optarg; 1239 break; 1240 1241 case 'R': 1242 Rflag = 0; 1243 break; 1244 1245 case 's': 1246 snaplen = strtol(optarg, &end, 0); 1247 if (optarg == end || *end != '\0' 1248 || snaplen < 0 || snaplen > MAXIMUM_SNAPLEN) 1249 error("invalid snaplen %s", optarg); 1250 else if (snaplen == 0) 1251 snaplen = MAXIMUM_SNAPLEN; 1252 break; 1253 1254 case 'S': 1255 ++Sflag; 1256 break; 1257 1258 case 't': 1259 ++tflag; 1260 break; 1261 1262 case 'T': 1263 if (strcasecmp(optarg, "vat") == 0) 1264 packettype = PT_VAT; 1265 else if (strcasecmp(optarg, "wb") == 0) 1266 packettype = PT_WB; 1267 else if (strcasecmp(optarg, "rpc") == 0) 1268 packettype = PT_RPC; 1269 else if (strcasecmp(optarg, "rtp") == 0) 1270 packettype = PT_RTP; 1271 else if (strcasecmp(optarg, "rtcp") == 0) 1272 packettype = PT_RTCP; 1273 else if (strcasecmp(optarg, "snmp") == 0) 1274 packettype = PT_SNMP; 1275 else if (strcasecmp(optarg, "cnfp") == 0) 1276 packettype = PT_CNFP; 1277 else if (strcasecmp(optarg, "tftp") == 0) 1278 packettype = PT_TFTP; 1279 else if (strcasecmp(optarg, "aodv") == 0) 1280 packettype = PT_AODV; 1281 else if (strcasecmp(optarg, "carp") == 0) 1282 packettype = PT_CARP; 1283 else if (strcasecmp(optarg, "radius") == 0) 1284 packettype = PT_RADIUS; 1285 else if (strcasecmp(optarg, "zmtp1") == 0) 1286 packettype = PT_ZMTP1; 1287 else if (strcasecmp(optarg, "vxlan") == 0) 1288 packettype = PT_VXLAN; 1289 else if (strcasecmp(optarg, "pgm") == 0) 1290 packettype = PT_PGM; 1291 else if (strcasecmp(optarg, "pgm_zmtp1") == 0) 1292 packettype = PT_PGM_ZMTP1; 1293 else if (strcasecmp(optarg, "lmp") == 0) 1294 packettype = PT_LMP; 1295 else 1296 error("unknown packet type `%s'", optarg); 1297 break; 1298 1299 case 'u': 1300 ++uflag; 1301 break; 1302 1303 #ifdef HAVE_PCAP_DUMP_FLUSH 1304 case 'U': 1305 ++Uflag; 1306 break; 1307 #endif 1308 1309 case 'v': 1310 ++vflag; 1311 break; 1312 1313 case 'V': 1314 VFileName = optarg; 1315 break; 1316 1317 case 'w': 1318 WFileName = optarg; 1319 break; 1320 1321 case 'W': 1322 Wflag = atoi(optarg); 1323 if (Wflag < 0) 1324 error("invalid number of output files %s", optarg); 1325 WflagChars = getWflagChars(Wflag); 1326 break; 1327 1328 case 'x': 1329 ++xflag; 1330 ++suppress_default_print; 1331 break; 1332 1333 case 'X': 1334 ++Xflag; 1335 ++suppress_default_print; 1336 break; 1337 1338 case 'y': 1339 gndo->ndo_dltname = optarg; 1340 gndo->ndo_dlt = 1341 pcap_datalink_name_to_val(gndo->ndo_dltname); 1342 if (gndo->ndo_dlt < 0) 1343 error("invalid data link type %s", gndo->ndo_dltname); 1344 break; 1345 1346 #if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG) 1347 case 'Y': 1348 { 1349 /* Undocumented flag */ 1350 #ifdef HAVE_PCAP_DEBUG 1351 extern int pcap_debug; 1352 pcap_debug = 1; 1353 #else 1354 extern int yydebug; 1355 yydebug = 1; 1356 #endif 1357 } 1358 break; 1359 #endif 1360 case 'z': 1361 zflag = strdup(optarg); 1362 break; 1363 1364 case 'Z': 1365 username = strdup(optarg); 1366 break; 1367 1368 case '#': 1369 gndo->ndo_packet_number = 1; 1370 break; 1371 1372 case OPTION_VERSION: 1373 print_version(); 1374 exit(0); 1375 break; 1376 1377 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION 1378 case OPTION_TSTAMP_PRECISION: 1379 gndo->ndo_tstamp_precision = tstamp_precision_from_string(optarg); 1380 if (gndo->ndo_tstamp_precision < 0) 1381 error("unsupported time stamp precision"); 1382 break; 1383 #endif 1384 1385 default: 1386 print_usage(); 1387 exit(1); 1388 /* NOTREACHED */ 1389 } 1390 1391 #ifdef HAVE_PCAP_FINDALLDEVS 1392 if (Dflag) 1393 show_devices_and_exit(); 1394 #endif 1395 1396 switch (tflag) { 1397 1398 case 0: /* Default */ 1399 case 4: /* Default + Date*/ 1400 thiszone = gmt2local(0); 1401 break; 1402 1403 case 1: /* No time stamp */ 1404 case 2: /* Unix timeval style */ 1405 case 3: /* Microseconds since previous packet */ 1406 case 5: /* Microseconds since first packet */ 1407 break; 1408 1409 default: /* Not supported */ 1410 error("only -t, -tt, -ttt, -tttt and -ttttt are supported"); 1411 break; 1412 } 1413 1414 if (fflag != 0 && (VFileName != NULL || RFileName != NULL)) 1415 error("-f can not be used with -V or -r"); 1416 1417 if (VFileName != NULL && RFileName != NULL) 1418 error("-V and -r are mutually exclusive."); 1419 1420 #ifdef WITH_CHROOT 1421 /* if run as root, prepare for chrooting */ 1422 if (getuid() == 0 || geteuid() == 0) { 1423 /* future extensibility for cmd-line arguments */ 1424 if (!chroot_dir) 1425 chroot_dir = WITH_CHROOT; 1426 } 1427 #endif 1428 1429 #ifdef WITH_USER 1430 /* if run as root, prepare for dropping root privileges */ 1431 if (getuid() == 0 || geteuid() == 0) { 1432 /* Run with '-Z root' to restore old behaviour */ 1433 if (!username) 1434 username = WITH_USER; 1435 } 1436 #endif 1437 1438 if (RFileName != NULL || VFileName != NULL) { 1439 /* 1440 * If RFileName is non-null, it's the pathname of a 1441 * savefile to read. If VFileName is non-null, it's 1442 * the pathname of a file containing a list of pathnames 1443 * (one per line) of savefiles to read. 1444 * 1445 * In either case, we're reading a savefile, not doing 1446 * a live capture. 1447 */ 1448 #ifndef WIN32 1449 /* 1450 * We don't need network access, so relinquish any set-UID 1451 * or set-GID privileges we have (if any). 1452 * 1453 * We do *not* want set-UID privileges when opening a 1454 * trace file, as that might let the user read other 1455 * people's trace files (especially if we're set-UID 1456 * root). 1457 */ 1458 if (setgid(getgid()) != 0 || setuid(getuid()) != 0 ) 1459 fprintf(stderr, "Warning: setgid/setuid failed !\n"); 1460 #endif /* WIN32 */ 1461 if (VFileName != NULL) { 1462 if (VFileName[0] == '-' && VFileName[1] == '\0') 1463 VFile = stdin; 1464 else 1465 VFile = fopen(VFileName, "r"); 1466 1467 if (VFile == NULL) 1468 error("Unable to open file: %s\n", strerror(errno)); 1469 1470 ret = get_next_file(VFile, VFileLine); 1471 if (!ret) 1472 error("Nothing in %s\n", VFileName); 1473 RFileName = VFileLine; 1474 } 1475 1476 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION 1477 pd = pcap_open_offline_with_tstamp_precision(RFileName, 1478 gndo->ndo_tstamp_precision, ebuf); 1479 #else 1480 pd = pcap_open_offline(RFileName, ebuf); 1481 #endif 1482 1483 if (pd == NULL) 1484 error("%s", ebuf); 1485 #ifdef HAVE_CAPSICUM 1486 cap_rights_init(&rights, CAP_READ); 1487 if (cap_rights_limit(fileno(pcap_file(pd)), &rights) < 0 && 1488 errno != ENOSYS) { 1489 error("unable to limit pcap descriptor"); 1490 } 1491 #endif 1492 dlt = pcap_datalink(pd); 1493 dlt_name = pcap_datalink_val_to_name(dlt); 1494 if (dlt_name == NULL) { 1495 fprintf(stderr, "reading from file %s, link-type %u\n", 1496 RFileName, dlt); 1497 } else { 1498 fprintf(stderr, 1499 "reading from file %s, link-type %s (%s)\n", 1500 RFileName, dlt_name, 1501 pcap_datalink_val_to_description(dlt)); 1502 } 1503 } else { 1504 /* 1505 * We're doing a live capture. 1506 */ 1507 if (device == NULL) { 1508 device = pcap_lookupdev(ebuf); 1509 if (device == NULL) 1510 error("%s", ebuf); 1511 } 1512 #ifdef WIN32 1513 /* 1514 * Print a message to the standard error on Windows. 1515 * XXX - why do it here, with a different message? 1516 */ 1517 if(strlen(device) == 1) /* we assume that an ASCII string is always longer than 1 char */ 1518 { /* a Unicode string has a \0 as second byte (so strlen() is 1) */ 1519 fprintf(stderr, "%s: listening on %ws\n", program_name, device); 1520 } 1521 else 1522 { 1523 fprintf(stderr, "%s: listening on %s\n", program_name, device); 1524 } 1525 1526 fflush(stderr); 1527 #endif /* WIN32 */ 1528 #ifdef HAVE_PCAP_CREATE 1529 pd = pcap_create(device, ebuf); 1530 if (pd == NULL) 1531 error("%s", ebuf); 1532 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE 1533 if (Jflag) 1534 show_tstamp_types_and_exit(device, pd); 1535 #endif 1536 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION 1537 status = pcap_set_tstamp_precision(pd, gndo->ndo_tstamp_precision); 1538 if (status != 0) 1539 error("%s: Can't set %ssecond time stamp precision: %s", 1540 device, 1541 tstamp_precision_to_string(gndo->ndo_tstamp_precision), 1542 pcap_statustostr(status)); 1543 #endif 1544 1545 /* 1546 * Is this an interface that supports monitor mode? 1547 */ 1548 if (pcap_can_set_rfmon(pd) == 1) 1549 supports_monitor_mode = 1; 1550 else 1551 supports_monitor_mode = 0; 1552 status = pcap_set_snaplen(pd, snaplen); 1553 if (status != 0) 1554 error("%s: Can't set snapshot length: %s", 1555 device, pcap_statustostr(status)); 1556 status = pcap_set_promisc(pd, !pflag); 1557 if (status != 0) 1558 error("%s: Can't set promiscuous mode: %s", 1559 device, pcap_statustostr(status)); 1560 if (Iflag) { 1561 status = pcap_set_rfmon(pd, 1); 1562 if (status != 0) 1563 error("%s: Can't set monitor mode: %s", 1564 device, pcap_statustostr(status)); 1565 } 1566 status = pcap_set_timeout(pd, 1000); 1567 if (status != 0) 1568 error("%s: pcap_set_timeout failed: %s", 1569 device, pcap_statustostr(status)); 1570 if (Bflag != 0) { 1571 status = pcap_set_buffer_size(pd, Bflag); 1572 if (status != 0) 1573 error("%s: Can't set buffer size: %s", 1574 device, pcap_statustostr(status)); 1575 } 1576 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE 1577 if (jflag != -1) { 1578 status = pcap_set_tstamp_type(pd, jflag); 1579 if (status < 0) 1580 error("%s: Can't set time stamp type: %s", 1581 device, pcap_statustostr(status)); 1582 } 1583 #endif 1584 status = pcap_activate(pd); 1585 if (status < 0) { 1586 /* 1587 * pcap_activate() failed. 1588 */ 1589 cp = pcap_geterr(pd); 1590 if (status == PCAP_ERROR) 1591 error("%s", cp); 1592 else if ((status == PCAP_ERROR_NO_SUCH_DEVICE || 1593 status == PCAP_ERROR_PERM_DENIED) && 1594 *cp != '\0') 1595 error("%s: %s\n(%s)", device, 1596 pcap_statustostr(status), cp); 1597 #ifdef __FreeBSD__ 1598 else if (status == PCAP_ERROR_RFMON_NOTSUP && 1599 strncmp(device, "wlan", 4) == 0) { 1600 char parent[8], newdev[8]; 1601 char sysctl[32]; 1602 size_t s = sizeof(parent); 1603 1604 snprintf(sysctl, sizeof(sysctl), 1605 "net.wlan.%d.%%parent", atoi(device + 4)); 1606 sysctlbyname(sysctl, parent, &s, NULL, 0); 1607 strlcpy(newdev, device, sizeof(newdev)); 1608 /* Suggest a new wlan device. */ 1609 newdev[strlen(newdev)-1]++; 1610 error("%s is not a monitor mode VAP\n" 1611 "To create a new monitor mode VAP use:\n" 1612 " ifconfig %s create wlandev %s wlanmode " 1613 "monitor\nand use %s as the tcpdump " 1614 "interface", device, newdev, parent, 1615 newdev); 1616 } 1617 #endif 1618 else 1619 error("%s: %s", device, 1620 pcap_statustostr(status)); 1621 } else if (status > 0) { 1622 /* 1623 * pcap_activate() succeeded, but it's warning us 1624 * of a problem it had. 1625 */ 1626 cp = pcap_geterr(pd); 1627 if (status == PCAP_WARNING) 1628 warning("%s", cp); 1629 else if (status == PCAP_WARNING_PROMISC_NOTSUP && 1630 *cp != '\0') 1631 warning("%s: %s\n(%s)", device, 1632 pcap_statustostr(status), cp); 1633 else 1634 warning("%s: %s", device, 1635 pcap_statustostr(status)); 1636 } 1637 #ifdef HAVE_PCAP_SETDIRECTION 1638 if (Qflag != -1) { 1639 status = pcap_setdirection(pd, Qflag); 1640 if (status != 0) 1641 error("%s: pcap_setdirection() failed: %s", 1642 device, pcap_geterr(pd)); 1643 } 1644 #endif /* HAVE_PCAP_SETDIRECTION */ 1645 #else 1646 *ebuf = '\0'; 1647 pd = pcap_open_live(device, snaplen, !pflag, 1000, ebuf); 1648 if (pd == NULL) 1649 error("%s", ebuf); 1650 else if (*ebuf) 1651 warning("%s", ebuf); 1652 #endif /* HAVE_PCAP_CREATE */ 1653 /* 1654 * Let user own process after socket has been opened. 1655 */ 1656 #ifndef WIN32 1657 if (setgid(getgid()) != 0 || setuid(getuid()) != 0) 1658 fprintf(stderr, "Warning: setgid/setuid failed !\n"); 1659 #endif /* WIN32 */ 1660 #if !defined(HAVE_PCAP_CREATE) && defined(WIN32) 1661 if(Bflag != 0) 1662 if(pcap_setbuff(pd, Bflag)==-1){ 1663 error("%s", pcap_geterr(pd)); 1664 } 1665 #endif /* !defined(HAVE_PCAP_CREATE) && defined(WIN32) */ 1666 if (Lflag) 1667 show_dlts_and_exit(device, pd); 1668 if (gndo->ndo_dlt >= 0) { 1669 #ifdef HAVE_PCAP_SET_DATALINK 1670 if (pcap_set_datalink(pd, gndo->ndo_dlt) < 0) 1671 error("%s", pcap_geterr(pd)); 1672 #else 1673 /* 1674 * We don't actually support changing the 1675 * data link type, so we only let them 1676 * set it to what it already is. 1677 */ 1678 if (gndo->ndo_dlt != pcap_datalink(pd)) { 1679 error("%s is not one of the DLTs supported by this device\n", 1680 gndo->ndo_dltname); 1681 } 1682 #endif 1683 (void)fprintf(stderr, "%s: data link type %s\n", 1684 program_name, gndo->ndo_dltname); 1685 (void)fflush(stderr); 1686 } 1687 i = pcap_snapshot(pd); 1688 if (snaplen < i) { 1689 warning("snaplen raised from %d to %d", snaplen, i); 1690 snaplen = i; 1691 } 1692 if(fflag != 0) { 1693 if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) { 1694 warning("foreign (-f) flag used but: %s", ebuf); 1695 } 1696 } 1697 1698 } 1699 if (infile) 1700 cmdbuf = read_infile(infile); 1701 else 1702 cmdbuf = copy_argv(&argv[optind]); 1703 1704 if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0) 1705 error("%s", pcap_geterr(pd)); 1706 if (dflag) { 1707 bpf_dump(&fcode, dflag); 1708 pcap_close(pd); 1709 free(cmdbuf); 1710 exit(0); 1711 } 1712 1713 #ifdef HAVE_CAPSICUM 1714 if (!nflag) 1715 capdns = capdns_setup(); 1716 #endif /* HAVE_CAPSICUM */ 1717 1718 init_addrtoname(gndo, localnet, netmask); 1719 init_checksum(); 1720 1721 #ifndef WIN32 1722 (void)setsignal(SIGPIPE, cleanup); 1723 (void)setsignal(SIGTERM, cleanup); 1724 (void)setsignal(SIGINT, cleanup); 1725 #endif /* WIN32 */ 1726 #if defined(HAVE_FORK) || defined(HAVE_VFORK) 1727 (void)setsignal(SIGCHLD, child_cleanup); 1728 #endif 1729 /* Cooperate with nohup(1) */ 1730 #ifndef WIN32 1731 if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL) 1732 (void)setsignal(SIGHUP, oldhandler); 1733 #endif /* WIN32 */ 1734 1735 #ifndef WIN32 1736 /* 1737 * If a user name was specified with "-Z", attempt to switch to 1738 * that user's UID. This would probably be used with sudo, 1739 * to allow tcpdump to be run in a special restricted 1740 * account (if you just want to allow users to open capture 1741 * devices, and can't just give users that permission, 1742 * you'd make tcpdump set-UID or set-GID). 1743 * 1744 * Tcpdump doesn't necessarily write only to one savefile; 1745 * the general only way to allow a -Z instance to write to 1746 * savefiles as the user under whose UID it's run, rather 1747 * than as the user specified with -Z, would thus be to switch 1748 * to the original user ID before opening a capture file and 1749 * then switch back to the -Z user ID after opening the savefile. 1750 * Switching to the -Z user ID only after opening the first 1751 * savefile doesn't handle the general case. 1752 */ 1753 1754 #ifdef HAVE_CAP_NG_H 1755 /* We are running as root and we will be writing to savefile */ 1756 if ((getuid() == 0 || geteuid() == 0) && WFileName) { 1757 if (username) { 1758 /* Drop all capabilities from effective set */ 1759 capng_clear(CAPNG_EFFECTIVE); 1760 /* Add capabilities we will need*/ 1761 capng_update(CAPNG_ADD, CAPNG_PERMITTED, CAP_SETUID); 1762 capng_update(CAPNG_ADD, CAPNG_PERMITTED, CAP_SETGID); 1763 capng_update(CAPNG_ADD, CAPNG_PERMITTED, CAP_DAC_OVERRIDE); 1764 1765 capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_SETUID); 1766 capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_SETGID); 1767 capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE); 1768 1769 capng_apply(CAPNG_SELECT_BOTH); 1770 } 1771 } 1772 #endif /* HAVE_CAP_NG_H */ 1773 1774 if (getuid() == 0 || geteuid() == 0) { 1775 if (username || chroot_dir) 1776 droproot(username, chroot_dir); 1777 1778 } 1779 #endif /* WIN32 */ 1780 1781 if (pcap_setfilter(pd, &fcode) < 0) 1782 error("%s", pcap_geterr(pd)); 1783 #ifdef HAVE_CAPSICUM 1784 if (RFileName == NULL && VFileName == NULL) { 1785 static const unsigned long cmds[] = { BIOCGSTATS }; 1786 1787 cap_rights_init(&rights, CAP_IOCTL, CAP_READ); 1788 if (cap_rights_limit(pcap_fileno(pd), &rights) < 0 && 1789 errno != ENOSYS) { 1790 error("unable to limit pcap descriptor"); 1791 } 1792 if (cap_ioctls_limit(pcap_fileno(pd), cmds, 1793 sizeof(cmds) / sizeof(cmds[0])) < 0 && errno != ENOSYS) { 1794 error("unable to limit ioctls on pcap descriptor"); 1795 } 1796 } 1797 #endif 1798 if (WFileName) { 1799 pcap_dumper_t *p; 1800 /* Do not exceed the default PATH_MAX for files. */ 1801 dumpinfo.CurrentFileName = (char *)malloc(PATH_MAX + 1); 1802 1803 if (dumpinfo.CurrentFileName == NULL) 1804 error("malloc of dumpinfo.CurrentFileName"); 1805 1806 /* We do not need numbering for dumpfiles if Cflag isn't set. */ 1807 if (Cflag != 0) 1808 MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, WflagChars); 1809 else 1810 MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, 0); 1811 1812 p = pcap_dump_open(pd, dumpinfo.CurrentFileName); 1813 #ifdef HAVE_CAP_NG_H 1814 /* Give up capabilities, clear Effective set */ 1815 capng_clear(CAPNG_EFFECTIVE); 1816 #endif 1817 if (p == NULL) 1818 error("%s", pcap_geterr(pd)); 1819 #ifdef HAVE_CAPSICUM 1820 cap_rights_init(&rights, CAP_SEEK, CAP_WRITE); 1821 if (cap_rights_limit(fileno(pcap_dump_file(p)), &rights) < 0 && 1822 errno != ENOSYS) { 1823 error("unable to limit dump descriptor"); 1824 } 1825 #endif 1826 if (Cflag != 0 || Gflag != 0) { 1827 #ifdef HAVE_CAPSICUM 1828 dumpinfo.WFileName = strdup(basename(WFileName)); 1829 dumpinfo.dirfd = open(dirname(WFileName), 1830 O_DIRECTORY | O_RDONLY); 1831 if (dumpinfo.dirfd < 0) { 1832 error("unable to open directory %s", 1833 dirname(WFileName)); 1834 } 1835 cap_rights_init(&rights, CAP_CREATE, CAP_FCNTL, 1836 CAP_FTRUNCATE, CAP_LOOKUP, CAP_SEEK, CAP_WRITE); 1837 if (cap_rights_limit(dumpinfo.dirfd, &rights) < 0 && 1838 errno != ENOSYS) { 1839 error("unable to limit directory rights"); 1840 } 1841 #else /* !HAVE_CAPSICUM */ 1842 dumpinfo.WFileName = WFileName; 1843 #endif 1844 callback = dump_packet_and_trunc; 1845 dumpinfo.pd = pd; 1846 dumpinfo.p = p; 1847 pcap_userdata = (u_char *)&dumpinfo; 1848 } else { 1849 callback = dump_packet; 1850 pcap_userdata = (u_char *)p; 1851 } 1852 #ifdef HAVE_PCAP_DUMP_FLUSH 1853 if (Uflag) 1854 pcap_dump_flush(p); 1855 #endif 1856 } else { 1857 type = pcap_datalink(pd); 1858 printinfo = get_print_info(type); 1859 callback = print_packet; 1860 pcap_userdata = (u_char *)&printinfo; 1861 } 1862 1863 #ifdef SIGNAL_REQ_INFO 1864 /* 1865 * We can't get statistics when reading from a file rather 1866 * than capturing from a device. 1867 */ 1868 if (RFileName == NULL) 1869 (void)setsignal(SIGNAL_REQ_INFO, requestinfo); 1870 #endif 1871 1872 if (vflag > 0 && WFileName) { 1873 /* 1874 * When capturing to a file, "-v" means tcpdump should, 1875 * every 10 secodns, "v"erbosely report the number of 1876 * packets captured. 1877 */ 1878 #ifdef USE_WIN32_MM_TIMER 1879 /* call verbose_stats_dump() each 1000 +/-100msec */ 1880 timer_id = timeSetEvent(1000, 100, verbose_stats_dump, 0, TIME_PERIODIC); 1881 setvbuf(stderr, NULL, _IONBF, 0); 1882 #elif defined(HAVE_ALARM) 1883 (void)setsignal(SIGALRM, verbose_stats_dump); 1884 alarm(1); 1885 #endif 1886 } 1887 1888 #ifndef WIN32 1889 if (RFileName == NULL) { 1890 /* 1891 * Live capture (if -V was specified, we set RFileName 1892 * to a file from the -V file). Print a message to 1893 * the standard error on UN*X. 1894 */ 1895 if (!vflag && !WFileName) { 1896 (void)fprintf(stderr, 1897 "%s: verbose output suppressed, use -v or -vv for full protocol decode\n", 1898 program_name); 1899 } else 1900 (void)fprintf(stderr, "%s: ", program_name); 1901 dlt = pcap_datalink(pd); 1902 dlt_name = pcap_datalink_val_to_name(dlt); 1903 if (dlt_name == NULL) { 1904 (void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n", 1905 device, dlt, snaplen); 1906 } else { 1907 (void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n", 1908 device, dlt_name, 1909 pcap_datalink_val_to_description(dlt), snaplen); 1910 } 1911 (void)fflush(stderr); 1912 } 1913 #endif /* WIN32 */ 1914 1915 #ifdef __FreeBSD__ 1916 cansandbox = (VFileName == NULL && zflag == NULL); 1917 #ifdef HAVE_CAPSICUM 1918 cansandbox = (cansandbox && (nflag || capdns != NULL)); 1919 #else 1920 cansandbox = (cansandbox && nflag); 1921 #endif 1922 if (cansandbox && cap_enter() < 0 && errno != ENOSYS) 1923 error("unable to enter the capability mode"); 1924 #endif /* __FreeBSD__ */ 1925 1926 do { 1927 status = pcap_loop(pd, cnt, callback, pcap_userdata); 1928 if (WFileName == NULL) { 1929 /* 1930 * We're printing packets. Flush the printed output, 1931 * so it doesn't get intermingled with error output. 1932 */ 1933 if (status == -2) { 1934 /* 1935 * We got interrupted, so perhaps we didn't 1936 * manage to finish a line we were printing. 1937 * Print an extra newline, just in case. 1938 */ 1939 putchar('\n'); 1940 } 1941 (void)fflush(stdout); 1942 } 1943 if (status == -2) { 1944 /* 1945 * We got interrupted. If we are reading multiple 1946 * files (via -V) set these so that we stop. 1947 */ 1948 VFileName = NULL; 1949 ret = NULL; 1950 } 1951 if (status == -1) { 1952 /* 1953 * Error. Report it. 1954 */ 1955 (void)fprintf(stderr, "%s: pcap_loop: %s\n", 1956 program_name, pcap_geterr(pd)); 1957 } 1958 if (RFileName == NULL) { 1959 /* 1960 * We're doing a live capture. Report the capture 1961 * statistics. 1962 */ 1963 info(1); 1964 } 1965 pcap_close(pd); 1966 if (VFileName != NULL) { 1967 ret = get_next_file(VFile, VFileLine); 1968 if (ret) { 1969 RFileName = VFileLine; 1970 pd = pcap_open_offline(RFileName, ebuf); 1971 if (pd == NULL) 1972 error("%s", ebuf); 1973 #ifdef HAVE_CAPSICUM 1974 cap_rights_init(&rights, CAP_READ); 1975 if (cap_rights_limit(fileno(pcap_file(pd)), 1976 &rights) < 0 && errno != ENOSYS) { 1977 error("unable to limit pcap descriptor"); 1978 } 1979 #endif 1980 new_dlt = pcap_datalink(pd); 1981 if (WFileName && new_dlt != dlt) 1982 error("%s: new dlt does not match original", RFileName); 1983 printinfo = get_print_info(new_dlt); 1984 dlt_name = pcap_datalink_val_to_name(new_dlt); 1985 if (dlt_name == NULL) { 1986 fprintf(stderr, "reading from file %s, link-type %u\n", 1987 RFileName, new_dlt); 1988 } else { 1989 fprintf(stderr, 1990 "reading from file %s, link-type %s (%s)\n", 1991 RFileName, dlt_name, 1992 pcap_datalink_val_to_description(new_dlt)); 1993 } 1994 if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0) 1995 error("%s", pcap_geterr(pd)); 1996 if (pcap_setfilter(pd, &fcode) < 0) 1997 error("%s", pcap_geterr(pd)); 1998 } 1999 } 2000 } 2001 while (ret != NULL); 2002 2003 free(cmdbuf); 2004 exit(status == -1 ? 1 : 0); 2005 } 2006 2007 /* make a clean exit on interrupts */ 2008 static RETSIGTYPE 2009 cleanup(int signo _U_) 2010 { 2011 #ifdef USE_WIN32_MM_TIMER 2012 if (timer_id) 2013 timeKillEvent(timer_id); 2014 timer_id = 0; 2015 #elif defined(HAVE_ALARM) 2016 alarm(0); 2017 #endif 2018 2019 #ifdef HAVE_PCAP_BREAKLOOP 2020 /* 2021 * We have "pcap_breakloop()"; use it, so that we do as little 2022 * as possible in the signal handler (it's probably not safe 2023 * to do anything with standard I/O streams in a signal handler - 2024 * the ANSI C standard doesn't say it is). 2025 */ 2026 pcap_breakloop(pd); 2027 #else 2028 /* 2029 * We don't have "pcap_breakloop()"; this isn't safe, but 2030 * it's the best we can do. Print the summary if we're 2031 * not reading from a savefile - i.e., if we're doing a 2032 * live capture - and exit. 2033 */ 2034 if (pd != NULL && pcap_file(pd) == NULL) { 2035 /* 2036 * We got interrupted, so perhaps we didn't 2037 * manage to finish a line we were printing. 2038 * Print an extra newline, just in case. 2039 */ 2040 putchar('\n'); 2041 (void)fflush(stdout); 2042 info(1); 2043 } 2044 exit(0); 2045 #endif 2046 } 2047 2048 /* 2049 On windows, we do not use a fork, so we do not care less about 2050 waiting a child processes to die 2051 */ 2052 #if defined(HAVE_FORK) || defined(HAVE_VFORK) 2053 static RETSIGTYPE 2054 child_cleanup(int signo _U_) 2055 { 2056 wait(NULL); 2057 } 2058 #endif /* HAVE_FORK && HAVE_VFORK */ 2059 2060 static void 2061 info(register int verbose) 2062 { 2063 struct pcap_stat stat; 2064 2065 /* 2066 * Older versions of libpcap didn't set ps_ifdrop on some 2067 * platforms; initialize it to 0 to handle that. 2068 */ 2069 stat.ps_ifdrop = 0; 2070 if (pcap_stats(pd, &stat) < 0) { 2071 (void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd)); 2072 infoprint = 0; 2073 return; 2074 } 2075 2076 if (!verbose) 2077 fprintf(stderr, "%s: ", program_name); 2078 2079 (void)fprintf(stderr, "%u packet%s captured", packets_captured, 2080 PLURAL_SUFFIX(packets_captured)); 2081 if (!verbose) 2082 fputs(", ", stderr); 2083 else 2084 putc('\n', stderr); 2085 (void)fprintf(stderr, "%u packet%s received by filter", stat.ps_recv, 2086 PLURAL_SUFFIX(stat.ps_recv)); 2087 if (!verbose) 2088 fputs(", ", stderr); 2089 else 2090 putc('\n', stderr); 2091 (void)fprintf(stderr, "%u packet%s dropped by kernel", stat.ps_drop, 2092 PLURAL_SUFFIX(stat.ps_drop)); 2093 if (stat.ps_ifdrop != 0) { 2094 if (!verbose) 2095 fputs(", ", stderr); 2096 else 2097 putc('\n', stderr); 2098 (void)fprintf(stderr, "%u packet%s dropped by interface\n", 2099 stat.ps_ifdrop, PLURAL_SUFFIX(stat.ps_ifdrop)); 2100 } else 2101 putc('\n', stderr); 2102 infoprint = 0; 2103 } 2104 2105 #if defined(HAVE_FORK) || defined(HAVE_VFORK) 2106 static void 2107 compress_savefile(const char *filename) 2108 { 2109 # ifdef HAVE_FORK 2110 if (fork()) 2111 # else 2112 if (vfork()) 2113 # endif 2114 return; 2115 /* 2116 * Set to lowest priority so that this doesn't disturb the capture 2117 */ 2118 #ifdef NZERO 2119 setpriority(PRIO_PROCESS, 0, NZERO - 1); 2120 #else 2121 setpriority(PRIO_PROCESS, 0, 19); 2122 #endif 2123 if (execlp(zflag, zflag, filename, (char *)NULL) == -1) 2124 fprintf(stderr, 2125 "compress_savefile:execlp(%s, %s): %s\n", 2126 zflag, 2127 filename, 2128 strerror(errno)); 2129 # ifdef HAVE_FORK 2130 exit(1); 2131 # else 2132 _exit(1); 2133 # endif 2134 } 2135 #else /* HAVE_FORK && HAVE_VFORK */ 2136 static void 2137 compress_savefile(const char *filename) 2138 { 2139 fprintf(stderr, 2140 "compress_savefile failed. Functionality not implemented under your system\n"); 2141 } 2142 #endif /* HAVE_FORK && HAVE_VFORK */ 2143 2144 static void 2145 dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) 2146 { 2147 struct dump_info *dump_info; 2148 #ifdef HAVE_CAPSICUM 2149 cap_rights_t rights; 2150 #endif 2151 2152 ++packets_captured; 2153 2154 ++infodelay; 2155 2156 dump_info = (struct dump_info *)user; 2157 2158 /* 2159 * XXX - this won't force the file to rotate on the specified time 2160 * boundary, but it will rotate on the first packet received after the 2161 * specified Gflag number of seconds. Note: if a Gflag time boundary 2162 * and a Cflag size boundary coincide, the time rotation will occur 2163 * first thereby cancelling the Cflag boundary (since the file should 2164 * be 0). 2165 */ 2166 if (Gflag != 0) { 2167 /* Check if it is time to rotate */ 2168 time_t t; 2169 2170 /* Get the current time */ 2171 if ((t = time(NULL)) == (time_t)-1) { 2172 error("dump_and_trunc_packet: can't get current_time: %s", 2173 pcap_strerror(errno)); 2174 } 2175 2176 2177 /* If the time is greater than the specified window, rotate */ 2178 if (t - Gflag_time >= Gflag) { 2179 #ifdef HAVE_CAPSICUM 2180 FILE *fp; 2181 int fd; 2182 #endif 2183 2184 /* Update the Gflag_time */ 2185 Gflag_time = t; 2186 /* Update Gflag_count */ 2187 Gflag_count++; 2188 /* 2189 * Close the current file and open a new one. 2190 */ 2191 pcap_dump_close(dump_info->p); 2192 2193 /* 2194 * Compress the file we just closed, if the user asked for it 2195 */ 2196 if (zflag != NULL) 2197 compress_savefile(dump_info->CurrentFileName); 2198 2199 /* 2200 * Check to see if we've exceeded the Wflag (when 2201 * not using Cflag). 2202 */ 2203 if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) { 2204 (void)fprintf(stderr, "Maximum file limit reached: %d\n", 2205 Wflag); 2206 exit(0); 2207 /* NOTREACHED */ 2208 } 2209 if (dump_info->CurrentFileName != NULL) 2210 free(dump_info->CurrentFileName); 2211 /* Allocate space for max filename + \0. */ 2212 dump_info->CurrentFileName = (char *)malloc(PATH_MAX + 1); 2213 if (dump_info->CurrentFileName == NULL) 2214 error("dump_packet_and_trunc: malloc"); 2215 /* 2216 * Gflag was set otherwise we wouldn't be here. Reset the count 2217 * so multiple files would end with 1,2,3 in the filename. 2218 * The counting is handled with the -C flow after this. 2219 */ 2220 Cflag_count = 0; 2221 2222 /* 2223 * This is always the first file in the Cflag 2224 * rotation: e.g. 0 2225 * We also don't need numbering if Cflag is not set. 2226 */ 2227 if (Cflag != 0) 2228 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0, 2229 WflagChars); 2230 else 2231 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0, 0); 2232 2233 #ifdef HAVE_CAP_NG_H 2234 capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE); 2235 capng_apply(CAPNG_EFFECTIVE); 2236 #endif /* HAVE_CAP_NG_H */ 2237 #ifdef HAVE_CAPSICUM 2238 fd = openat(dump_info->dirfd, 2239 dump_info->CurrentFileName, 2240 O_CREAT | O_WRONLY | O_TRUNC, 0644); 2241 if (fd < 0) { 2242 error("unable to open file %s", 2243 dump_info->CurrentFileName); 2244 } 2245 fp = fdopen(fd, "w"); 2246 if (fp == NULL) { 2247 error("unable to fdopen file %s", 2248 dump_info->CurrentFileName); 2249 } 2250 dump_info->p = pcap_dump_fopen(dump_info->pd, fp); 2251 #else /* !HAVE_CAPSICUM */ 2252 dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName); 2253 #endif 2254 #ifdef HAVE_CAP_NG_H 2255 capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE); 2256 capng_apply(CAPNG_EFFECTIVE); 2257 #endif /* HAVE_CAP_NG_H */ 2258 if (dump_info->p == NULL) 2259 error("%s", pcap_geterr(pd)); 2260 #ifdef HAVE_CAPSICUM 2261 cap_rights_init(&rights, CAP_SEEK, CAP_WRITE); 2262 if (cap_rights_limit(fileno(pcap_dump_file(dump_info->p)), 2263 &rights) < 0 && errno != ENOSYS) { 2264 error("unable to limit dump descriptor"); 2265 } 2266 #endif 2267 } 2268 } 2269 2270 /* 2271 * XXX - this won't prevent capture files from getting 2272 * larger than Cflag - the last packet written to the 2273 * file could put it over Cflag. 2274 */ 2275 if (Cflag != 0 && pcap_dump_ftell(dump_info->p) > Cflag) { 2276 #ifdef HAVE_CAPSICUM 2277 FILE *fp; 2278 int fd; 2279 #endif 2280 2281 /* 2282 * Close the current file and open a new one. 2283 */ 2284 pcap_dump_close(dump_info->p); 2285 2286 /* 2287 * Compress the file we just closed, if the user asked for it 2288 */ 2289 if (zflag != NULL) 2290 compress_savefile(dump_info->CurrentFileName); 2291 2292 Cflag_count++; 2293 if (Wflag > 0) { 2294 if (Cflag_count >= Wflag) 2295 Cflag_count = 0; 2296 } 2297 if (dump_info->CurrentFileName != NULL) 2298 free(dump_info->CurrentFileName); 2299 dump_info->CurrentFileName = (char *)malloc(PATH_MAX + 1); 2300 if (dump_info->CurrentFileName == NULL) 2301 error("dump_packet_and_trunc: malloc"); 2302 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, Cflag_count, WflagChars); 2303 #ifdef HAVE_CAPSICUM 2304 fd = openat(dump_info->dirfd, dump_info->CurrentFileName, 2305 O_CREAT | O_WRONLY | O_TRUNC, 0644); 2306 if (fd < 0) { 2307 error("unable to open file %s", 2308 dump_info->CurrentFileName); 2309 } 2310 fp = fdopen(fd, "w"); 2311 if (fp == NULL) { 2312 error("unable to fdopen file %s", 2313 dump_info->CurrentFileName); 2314 } 2315 dump_info->p = pcap_dump_fopen(dump_info->pd, fp); 2316 #else /* !HAVE_CAPSICUM */ 2317 dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName); 2318 #endif 2319 if (dump_info->p == NULL) 2320 error("%s", pcap_geterr(pd)); 2321 #ifdef HAVE_CAPSICUM 2322 cap_rights_init(&rights, CAP_SEEK, CAP_WRITE); 2323 if (cap_rights_limit(fileno(pcap_dump_file(dump_info->p)), 2324 &rights) < 0 && errno != ENOSYS) { 2325 error("unable to limit dump descriptor"); 2326 } 2327 #endif 2328 } 2329 2330 pcap_dump((u_char *)dump_info->p, h, sp); 2331 #ifdef HAVE_PCAP_DUMP_FLUSH 2332 if (Uflag) 2333 pcap_dump_flush(dump_info->p); 2334 #endif 2335 2336 --infodelay; 2337 if (infoprint) 2338 info(0); 2339 } 2340 2341 static void 2342 dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) 2343 { 2344 ++packets_captured; 2345 2346 ++infodelay; 2347 2348 pcap_dump(user, h, sp); 2349 #ifdef HAVE_PCAP_DUMP_FLUSH 2350 if (Uflag) 2351 pcap_dump_flush((pcap_dumper_t *)user); 2352 #endif 2353 2354 --infodelay; 2355 if (infoprint) 2356 info(0); 2357 } 2358 2359 static void 2360 print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) 2361 { 2362 struct print_info *print_info; 2363 u_int hdrlen; 2364 netdissect_options *ndo; 2365 2366 ++packets_captured; 2367 2368 ++infodelay; 2369 2370 print_info = (struct print_info *)user; 2371 ndo = print_info->ndo; 2372 2373 if(ndo->ndo_packet_number) 2374 ND_PRINT((ndo, "%5u ", packets_captured)); 2375 2376 ts_print(ndo, &h->ts); 2377 2378 /* 2379 * Some printers want to check that they're not walking off the 2380 * end of the packet. 2381 * Rather than pass it all the way down, we set this global. 2382 */ 2383 ndo->ndo_snapend = sp + h->caplen; 2384 2385 if(print_info->ndo_type) { 2386 hdrlen = (*print_info->p.ndo_printer)(print_info->ndo, h, sp); 2387 } else { 2388 hdrlen = (*print_info->p.printer)(h, sp); 2389 } 2390 2391 if (ndo->ndo_Xflag) { 2392 /* 2393 * Print the raw packet data in hex and ASCII. 2394 */ 2395 if (ndo->ndo_Xflag > 1) { 2396 /* 2397 * Include the link-layer header. 2398 */ 2399 hex_and_ascii_print(ndo, "\n\t", sp, h->caplen); 2400 } else { 2401 /* 2402 * Don't include the link-layer header - and if 2403 * we have nothing past the link-layer header, 2404 * print nothing. 2405 */ 2406 if (h->caplen > hdrlen) 2407 hex_and_ascii_print(ndo, "\n\t", sp + hdrlen, 2408 h->caplen - hdrlen); 2409 } 2410 } else if (ndo->ndo_xflag) { 2411 /* 2412 * Print the raw packet data in hex. 2413 */ 2414 if (ndo->ndo_xflag > 1) { 2415 /* 2416 * Include the link-layer header. 2417 */ 2418 hex_print(ndo, "\n\t", sp, h->caplen); 2419 } else { 2420 /* 2421 * Don't include the link-layer header - and if 2422 * we have nothing past the link-layer header, 2423 * print nothing. 2424 */ 2425 if (h->caplen > hdrlen) 2426 hex_print(ndo, "\n\t", sp + hdrlen, 2427 h->caplen - hdrlen); 2428 } 2429 } else if (ndo->ndo_Aflag) { 2430 /* 2431 * Print the raw packet data in ASCII. 2432 */ 2433 if (ndo->ndo_Aflag > 1) { 2434 /* 2435 * Include the link-layer header. 2436 */ 2437 ascii_print(ndo, sp, h->caplen); 2438 } else { 2439 /* 2440 * Don't include the link-layer header - and if 2441 * we have nothing past the link-layer header, 2442 * print nothing. 2443 */ 2444 if (h->caplen > hdrlen) 2445 ascii_print(ndo, sp + hdrlen, h->caplen - hdrlen); 2446 } 2447 } 2448 2449 putchar('\n'); 2450 2451 --infodelay; 2452 if (infoprint) 2453 info(0); 2454 } 2455 2456 #ifdef WIN32 2457 /* 2458 * XXX - there should really be libpcap calls to get the version 2459 * number as a string (the string would be generated from #defines 2460 * at run time, so that it's not generated from string constants 2461 * in the library, as, on many UNIX systems, those constants would 2462 * be statically linked into the application executable image, and 2463 * would thus reflect the version of libpcap on the system on 2464 * which the application was *linked*, not the system on which it's 2465 * *running*. 2466 * 2467 * That routine should be documented, unlike the "version[]" 2468 * string, so that UNIX vendors providing their own libpcaps 2469 * don't omit it (as a couple of vendors have...). 2470 * 2471 * Packet.dll should perhaps also export a routine to return the 2472 * version number of the Packet.dll code, to supply the 2473 * "Wpcap_version" information on Windows. 2474 */ 2475 char WDversion[]="current-git.tcpdump.org"; 2476 #if !defined(HAVE_GENERATED_VERSION) 2477 char version[]="current-git.tcpdump.org"; 2478 #endif 2479 char pcap_version[]="current-git.tcpdump.org"; 2480 char Wpcap_version[]="3.1"; 2481 #endif 2482 2483 /* 2484 * By default, print the specified data out in hex and ASCII. 2485 */ 2486 static void 2487 ndo_default_print(netdissect_options *ndo, const u_char *bp, u_int length) 2488 { 2489 hex_and_ascii_print(ndo, "\n\t", bp, length); /* pass on lf and identation string */ 2490 } 2491 2492 void 2493 default_print(const u_char *bp, u_int length) 2494 { 2495 ndo_default_print(gndo, bp, length); 2496 } 2497 2498 #ifdef SIGNAL_REQ_INFO 2499 RETSIGTYPE requestinfo(int signo _U_) 2500 { 2501 if (infodelay) 2502 ++infoprint; 2503 else 2504 info(0); 2505 } 2506 #endif 2507 2508 /* 2509 * Called once each second in verbose mode while dumping to file 2510 */ 2511 #ifdef USE_WIN32_MM_TIMER 2512 void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_, 2513 DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_) 2514 { 2515 struct pcap_stat stat; 2516 2517 if (infodelay == 0 && pcap_stats(pd, &stat) >= 0) 2518 fprintf(stderr, "Got %u\r", packets_captured); 2519 } 2520 #elif defined(HAVE_ALARM) 2521 static void verbose_stats_dump(int sig _U_) 2522 { 2523 struct pcap_stat stat; 2524 2525 if (infodelay == 0 && pcap_stats(pd, &stat) >= 0) 2526 fprintf(stderr, "Got %u\r", packets_captured); 2527 alarm(1); 2528 } 2529 #endif 2530 2531 USES_APPLE_DEPRECATED_API 2532 static void 2533 print_version(void) 2534 { 2535 extern char version[]; 2536 #ifndef HAVE_PCAP_LIB_VERSION 2537 #if defined(WIN32) || defined(HAVE_PCAP_VERSION) 2538 extern char pcap_version[]; 2539 #else /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */ 2540 static char pcap_version[] = "unknown"; 2541 #endif /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */ 2542 #endif /* HAVE_PCAP_LIB_VERSION */ 2543 2544 #ifdef HAVE_PCAP_LIB_VERSION 2545 #ifdef WIN32 2546 (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version); 2547 #else /* WIN32 */ 2548 (void)fprintf(stderr, "%s version %s\n", program_name, version); 2549 #endif /* WIN32 */ 2550 (void)fprintf(stderr, "%s\n",pcap_lib_version()); 2551 #else /* HAVE_PCAP_LIB_VERSION */ 2552 #ifdef WIN32 2553 (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version); 2554 (void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version); 2555 #else /* WIN32 */ 2556 (void)fprintf(stderr, "%s version %s\n", program_name, version); 2557 (void)fprintf(stderr, "libpcap version %s\n", pcap_version); 2558 #endif /* WIN32 */ 2559 #endif /* HAVE_PCAP_LIB_VERSION */ 2560 2561 #if defined(HAVE_LIBCRYPTO) && defined(SSLEAY_VERSION) 2562 (void)fprintf (stderr, "%s\n", SSLeay_version(SSLEAY_VERSION)); 2563 #endif 2564 2565 #ifdef USE_LIBSMI 2566 (void)fprintf (stderr, "SMI-library: %s\n", smi_version_string); 2567 #endif 2568 } 2569 USES_APPLE_RST 2570 2571 static void 2572 print_usage(void) 2573 { 2574 print_version(); 2575 (void)fprintf(stderr, 2576 "Usage: %s [-aAbd" D_FLAG "efhH" I_FLAG J_FLAG "KlLnNOpqRStu" U_FLAG "vxX#]" B_FLAG_USAGE " [ -c count ]\n", program_name); 2577 (void)fprintf(stderr, 2578 "\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n"); 2579 (void)fprintf(stderr, 2580 "\t\t[ -i interface ]" j_FLAG_USAGE " [ -M secret ] [ --number ]\n"); 2581 #ifdef HAVE_PCAP_SETDIRECTION 2582 (void)fprintf(stderr, 2583 "\t\t[ -Q in|out|inout ]\n"); 2584 #endif 2585 (void)fprintf(stderr, 2586 "\t\t[ -r file ] [ -s snaplen ] "); 2587 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION 2588 (void)fprintf(stderr, "[ --time-stamp-precision precision ]\n"); 2589 (void)fprintf(stderr, 2590 "\t\t"); 2591 #endif 2592 (void)fprintf(stderr, "[ -T type ] [ --version ] [ -V file ]\n"); 2593 (void)fprintf(stderr, 2594 "\t\t[ -w file ] [ -W filecount ] [ -y datalinktype ] [ -z command ]\n"); 2595 (void)fprintf(stderr, 2596 "\t\t[ -Z user ] [ expression ]\n"); 2597 } 2598 2599 2600 2601 /* VARARGS */ 2602 static void 2603 ndo_error(netdissect_options *ndo _U_, const char *fmt, ...) 2604 { 2605 va_list ap; 2606 2607 (void)fprintf(stderr, "%s: ", program_name); 2608 va_start(ap, fmt); 2609 (void)vfprintf(stderr, fmt, ap); 2610 va_end(ap); 2611 if (*fmt) { 2612 fmt += strlen(fmt); 2613 if (fmt[-1] != '\n') 2614 (void)fputc('\n', stderr); 2615 } 2616 exit(1); 2617 /* NOTREACHED */ 2618 } 2619 2620 /* VARARGS */ 2621 static void 2622 ndo_warning(netdissect_options *ndo _U_, const char *fmt, ...) 2623 { 2624 va_list ap; 2625 2626 (void)fprintf(stderr, "%s: WARNING: ", program_name); 2627 va_start(ap, fmt); 2628 (void)vfprintf(stderr, fmt, ap); 2629 va_end(ap); 2630 if (*fmt) { 2631 fmt += strlen(fmt); 2632 if (fmt[-1] != '\n') 2633 (void)fputc('\n', stderr); 2634 } 2635 } 2636 /* 2637 * Local Variables: 2638 * c-style: whitesmith 2639 * c-basic-offset: 8 2640 * End: 2641 */ 2642