diff options
Diffstat (limited to 'tcpdump.c')
| -rw-r--r-- | tcpdump.c | 2649 |
1 files changed, 2649 insertions, 0 deletions
diff --git a/tcpdump.c b/tcpdump.c new file mode 100644 index 000000000000..043bda1d7aca --- /dev/null +++ b/tcpdump.c @@ -0,0 +1,2649 @@ +/* + * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that: (1) source code distributions + * retain the above copyright notice and this paragraph in its entirety, (2) + * distributions including binary code include the above copyright notice and + * this paragraph in its entirety in the documentation or other materials + * provided with the distribution, and (3) all advertising materials mentioning + * features or use of this software display the following acknowledgement: + * ``This product includes software developed by the University of California, + * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of + * the University nor the names of its contributors may be used to endorse + * or promote products derived from this software without specific prior + * written permission. + * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. + * + * Support for splitting captures into multiple files with a maximum + * file size: + * + * Copyright (c) 2001 + * Seth Webster <swebster@sst.ll.mit.edu> + */ + +#ifndef lint +static const char copyright[] _U_ = + "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\ +The Regents of the University of California. All rights reserved.\n"; +#endif + +/* + * tcpdump - dump traffic on a network + * + * First written in 1987 by Van Jacobson, Lawrence Berkeley Laboratory. + * Mercilessly hacked and occasionally improved since then via the + * combined efforts of Van, Steve McCanne and Craig Leres of LBL. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +/* + * Mac OS X may ship pcap.h from libpcap 0.6 with a libpcap based on + * 0.8. That means it has pcap_findalldevs() but the header doesn't + * define pcap_if_t, meaning that we can't actually *use* pcap_findalldevs(). + */ +#ifdef HAVE_PCAP_FINDALLDEVS +#ifndef HAVE_PCAP_IF_T +#undef HAVE_PCAP_FINDALLDEVS +#endif +#endif + +#include <netdissect-stdinc.h> + +#include <sys/stat.h> + +#ifdef HAVE_FCNTL_H +#include <fcntl.h> +#endif + +#ifdef HAVE_LIBCRYPTO +#include <openssl/crypto.h> +#endif + +#ifdef HAVE_GETOPT_LONG +#include <getopt.h> +#else +#include "getopt_long.h" +#endif +/* Capsicum-specific code requires macros from <net/bpf.h>, which will fail + * to compile if <pcap.h> has already been included; including the headers + * in the opposite order works fine. + */ +#ifdef HAVE_CAPSICUM +#include <sys/capability.h> +#include <sys/ioccom.h> +#include <net/bpf.h> +#include <libgen.h> +#endif /* HAVE_CAPSICUM */ +#include <pcap.h> +#include <signal.h> +#include <stdio.h> +#include <stdarg.h> +#include <stdlib.h> +#include <string.h> +#include <limits.h> +#ifndef _WIN32 +#include <sys/wait.h> +#include <sys/resource.h> +#include <pwd.h> +#include <grp.h> +#endif /* _WIN32 */ + +/* capabilities convenience library */ +/* If a code depends on HAVE_LIBCAP_NG, it depends also on HAVE_CAP_NG_H. + * If HAVE_CAP_NG_H is not defined, undefine HAVE_LIBCAP_NG. + * Thus, the later tests are done only on HAVE_LIBCAP_NG. + */ +#ifdef HAVE_LIBCAP_NG +#ifdef HAVE_CAP_NG_H +#include <cap-ng.h> +#else +#undef HAVE_LIBCAP_NG +#endif /* HAVE_CAP_NG_H */ +#endif /* HAVE_LIBCAP_NG */ + +#include "netdissect.h" +#include "interface.h" +#include "addrtoname.h" +#include "machdep.h" +#include "setsignal.h" +#include "gmt2local.h" +#include "pcap-missing.h" +#include "ascii_strcasecmp.h" + +#include "print.h" + +#ifndef PATH_MAX +#define PATH_MAX 1024 +#endif + +#ifdef SIGINFO +#define SIGNAL_REQ_INFO SIGINFO +#elif SIGUSR1 +#define SIGNAL_REQ_INFO SIGUSR1 +#endif + +static int Bflag; /* buffer size */ +static long Cflag; /* rotate dump files after this many bytes */ +static int Cflag_count; /* Keep track of which file number we're writing */ +static int Dflag; /* list available devices and exit */ +/* + * This is exported because, in some versions of libpcap, if libpcap + * is built with optimizer debugging code (which is *NOT* the default + * configuration!), the library *imports*(!) a variable named dflag, + * under the expectation that tcpdump is exporting it, to govern + * how much debugging information to print when optimizing + * the generated BPF code. + * + * This is a horrible hack; newer versions of libpcap don't import + * dflag but, instead, *if* built with optimizer debugging code, + * *export* a routine to set that flag. + */ +int dflag; /* print filter code */ +static int Gflag; /* rotate dump files after this many seconds */ +static int Gflag_count; /* number of files created with Gflag rotation */ +static time_t Gflag_time; /* The last time_t the dump file was rotated. */ +static int Lflag; /* list available data link types and exit */ +static int Iflag; /* rfmon (monitor) mode */ +#ifdef HAVE_PCAP_SET_TSTAMP_TYPE +static int Jflag; /* list available time stamp types */ +#endif +static int jflag = -1; /* packet time stamp source */ +static int pflag; /* don't go promiscuous */ +#ifdef HAVE_PCAP_SETDIRECTION +static int Qflag = -1; /* restrict captured packet by send/receive direction */ +#endif +static int Uflag; /* "unbuffered" output of dump files */ +static int Wflag; /* recycle output files after this number of files */ +static int WflagChars; +static char *zflag = NULL; /* compress each savefile using a specified command (like gzip or bzip2) */ +static int immediate_mode; + +static int infodelay; +static int infoprint; + +char *program_name; + +/* Forwards */ +static void error(FORMAT_STRING(const char *), ...) NORETURN PRINTFLIKE(1, 2); +static void warning(FORMAT_STRING(const char *), ...) PRINTFLIKE(1, 2); +static void exit_tcpdump(int) NORETURN; +static RETSIGTYPE cleanup(int); +static RETSIGTYPE child_cleanup(int); +static void print_version(void); +static void print_usage(void); +static void show_tstamp_types_and_exit(pcap_t *, const char *device) NORETURN; +static void show_dlts_and_exit(pcap_t *, const char *device) NORETURN; +#ifdef HAVE_PCAP_FINDALLDEVS +static void show_devices_and_exit (void) NORETURN; +#endif + +static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *); +static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *); +static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *); +static void droproot(const char *, const char *); + +#ifdef SIGNAL_REQ_INFO +RETSIGTYPE requestinfo(int); +#endif + +#if defined(USE_WIN32_MM_TIMER) + #include <MMsystem.h> + static UINT timer_id; + static void CALLBACK verbose_stats_dump(UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR); +#elif defined(HAVE_ALARM) + static void verbose_stats_dump(int sig); +#endif + +static void info(int); +static u_int packets_captured; + +#ifdef HAVE_PCAP_FINDALLDEVS +static const struct tok status_flags[] = { +#ifdef PCAP_IF_UP + { PCAP_IF_UP, "Up" }, +#endif +#ifdef PCAP_IF_RUNNING + { PCAP_IF_RUNNING, "Running" }, +#endif + { PCAP_IF_LOOPBACK, "Loopback" }, + { 0, NULL } +}; +#endif + +static pcap_t *pd; + +static int supports_monitor_mode; + +extern int optind; +extern int opterr; +extern char *optarg; + +struct dump_info { + char *WFileName; + char *CurrentFileName; + pcap_t *pd; + pcap_dumper_t *p; +#ifdef HAVE_CAPSICUM + int dirfd; +#endif +}; + +#if defined(HAVE_PCAP_SET_PARSER_DEBUG) +/* + * We have pcap_set_parser_debug() in libpcap; declare it (it's not declared + * by any libpcap header, because it's a special hack, only available if + * libpcap was configured to include it, and only intended for use by + * libpcap developers trying to debug the parser for filter expressions). + */ +#ifdef _WIN32 +__declspec(dllimport) +#else /* _WIN32 */ +extern +#endif /* _WIN32 */ +void pcap_set_parser_debug(int); +#elif defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG) +/* + * We don't have pcap_set_parser_debug() in libpcap, but we do have + * pcap_debug or yydebug. Make a local version of pcap_set_parser_debug() + * to set the flag, and define HAVE_PCAP_SET_PARSER_DEBUG. + */ +static void +pcap_set_parser_debug(int value) +{ +#ifdef HAVE_PCAP_DEBUG + extern int pcap_debug; + + pcap_debug = value; +#else /* HAVE_PCAP_DEBUG */ + extern int yydebug; + + yydebug = value; +#endif /* HAVE_PCAP_DEBUG */ +} + +#define HAVE_PCAP_SET_PARSER_DEBUG +#endif + +#if defined(HAVE_PCAP_SET_OPTIMIZER_DEBUG) +/* + * We have pcap_set_optimizer_debug() in libpcap; declare it (it's not declared + * by any libpcap header, because it's a special hack, only available if + * libpcap was configured to include it, and only intended for use by + * libpcap developers trying to debug the optimizer for filter expressions). + */ +#ifdef _WIN32 +__declspec(dllimport) +#else /* _WIN32 */ +extern +#endif /* _WIN32 */ +void pcap_set_optimizer_debug(int); +#endif + +/* VARARGS */ +static void +error(const char *fmt, ...) +{ + va_list ap; + + (void)fprintf(stderr, "%s: ", program_name); + va_start(ap, fmt); + (void)vfprintf(stderr, fmt, ap); + va_end(ap); + if (*fmt) { + fmt += strlen(fmt); + if (fmt[-1] != '\n') + (void)fputc('\n', stderr); + } + exit_tcpdump(1); + /* NOTREACHED */ +} + +/* VARARGS */ +static void +warning(const char *fmt, ...) +{ + va_list ap; + + (void)fprintf(stderr, "%s: WARNING: ", program_name); + va_start(ap, fmt); + (void)vfprintf(stderr, fmt, ap); + va_end(ap); + if (*fmt) { + fmt += strlen(fmt); + if (fmt[-1] != '\n') + (void)fputc('\n', stderr); + } +} + +static void +exit_tcpdump(int status) +{ + nd_cleanup(); + exit(status); +} + +#ifdef HAVE_PCAP_SET_TSTAMP_TYPE +static void +show_tstamp_types_and_exit(pcap_t *pc, const char *device) +{ + int n_tstamp_types; + int *tstamp_types = 0; + const char *tstamp_type_name; + int i; + + n_tstamp_types = pcap_list_tstamp_types(pc, &tstamp_types); + if (n_tstamp_types < 0) + error("%s", pcap_geterr(pc)); + + if (n_tstamp_types == 0) { + fprintf(stderr, "Time stamp type cannot be set for %s\n", + device); + exit_tcpdump(0); + } + fprintf(stderr, "Time stamp types for %s (use option -j to set):\n", + device); + for (i = 0; i < n_tstamp_types; i++) { + tstamp_type_name = pcap_tstamp_type_val_to_name(tstamp_types[i]); + if (tstamp_type_name != NULL) { + (void) fprintf(stderr, " %s (%s)\n", tstamp_type_name, + pcap_tstamp_type_val_to_description(tstamp_types[i])); + } else { + (void) fprintf(stderr, " %d\n", tstamp_types[i]); + } + } + pcap_free_tstamp_types(tstamp_types); + exit_tcpdump(0); +} +#endif + +static void +show_dlts_and_exit(pcap_t *pc, const char *device) +{ + int n_dlts, i; + int *dlts = 0; + const char *dlt_name; + + n_dlts = pcap_list_datalinks(pc, &dlts); + if (n_dlts < 0) + error("%s", pcap_geterr(pc)); + else if (n_dlts == 0 || !dlts) + error("No data link types."); + + /* + * If the interface is known to support monitor mode, indicate + * whether these are the data link types available when not in + * monitor mode, if -I wasn't specified, or when in monitor mode, + * when -I was specified (the link-layer types available in + * monitor mode might be different from the ones available when + * not in monitor mode). + */ + if (supports_monitor_mode) + (void) fprintf(stderr, "Data link types for %s %s (use option -y to set):\n", + device, + Iflag ? "when in monitor mode" : "when not in monitor mode"); + else + (void) fprintf(stderr, "Data link types for %s (use option -y to set):\n", + device); + + for (i = 0; i < n_dlts; i++) { + dlt_name = pcap_datalink_val_to_name(dlts[i]); + if (dlt_name != NULL) { + (void) fprintf(stderr, " %s (%s)", dlt_name, + pcap_datalink_val_to_description(dlts[i])); + + /* + * OK, does tcpdump handle that type? + */ + if (!has_printer(dlts[i])) + (void) fprintf(stderr, " (printing not supported)"); + fprintf(stderr, "\n"); + } else { + (void) fprintf(stderr, " DLT %d (printing not supported)\n", + dlts[i]); + } + } +#ifdef HAVE_PCAP_FREE_DATALINKS + pcap_free_datalinks(dlts); +#endif + exit_tcpdump(0); +} + +#ifdef HAVE_PCAP_FINDALLDEVS +static void +show_devices_and_exit (void) +{ + pcap_if_t *dev, *devlist; + char ebuf[PCAP_ERRBUF_SIZE]; + int i; + + if (pcap_findalldevs(&devlist, ebuf) < 0) + error("%s", ebuf); + for (i = 0, dev = devlist; dev != NULL; i++, dev = dev->next) { + printf("%d.%s", i+1, dev->name); + if (dev->description != NULL) + printf(" (%s)", dev->description); + if (dev->flags != 0) + printf(" [%s]", bittok2str(status_flags, "none", dev->flags)); + printf("\n"); + } + pcap_freealldevs(devlist); + exit_tcpdump(0); +} +#endif /* HAVE_PCAP_FINDALLDEVS */ + +/* + * Short options. + * + * Note that there we use all letters for short options except for g, k, + * o, and P, and those are used by other versions of tcpdump, and we should + * only use them for the same purposes that the other versions of tcpdump + * use them: + * + * OS X tcpdump uses -g to force non--v output for IP to be on one + * line, making it more "g"repable; + * + * OS X tcpdump uses -k to specify that packet comments in pcap-ng files + * should be printed; + * + * OpenBSD tcpdump uses -o to indicate that OS fingerprinting should be done + * for hosts sending TCP SYN packets; + * + * OS X tcpdump uses -P to indicate that -w should write pcap-ng rather + * than pcap files. + * + * OS X tcpdump also uses -Q to specify expressions that match packet + * metadata, including but not limited to the packet direction. + * The expression syntax is different from a simple "in|out|inout", + * and those expressions aren't accepted by OS X tcpdump, but the + * equivalents would be "in" = "dir=in", "out" = "dir=out", and + * "inout" = "dir=in or dir=out", and the parser could conceivably + * special-case "in", "out", and "inout" as expressions for backwards + * compatibility, so all is not (yet) lost. + */ + +/* + * Set up flags that might or might not be supported depending on the + * version of libpcap we're using. + */ +#if defined(HAVE_PCAP_CREATE) || defined(_WIN32) +#define B_FLAG "B:" +#define B_FLAG_USAGE " [ -B size ]" +#else /* defined(HAVE_PCAP_CREATE) || defined(_WIN32) */ +#define B_FLAG +#define B_FLAG_USAGE +#endif /* defined(HAVE_PCAP_CREATE) || defined(_WIN32) */ + +#ifdef HAVE_PCAP_CREATE +#define I_FLAG "I" +#else /* HAVE_PCAP_CREATE */ +#define I_FLAG +#endif /* HAVE_PCAP_CREATE */ + +#ifdef HAVE_PCAP_SET_TSTAMP_TYPE +#define j_FLAG "j:" +#define j_FLAG_USAGE " [ -j tstamptype ]" +#define J_FLAG "J" +#else /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */ +#define j_FLAG +#define j_FLAG_USAGE +#define J_FLAG +#endif /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */ + +#ifdef HAVE_PCAP_FINDALLDEVS +#define D_FLAG "D" +#else +#define D_FLAG +#endif + +#ifdef HAVE_PCAP_DUMP_FLUSH +#define U_FLAG "U" +#else +#define U_FLAG +#endif + +#ifdef HAVE_PCAP_SETDIRECTION +#define Q_FLAG "Q:" +#else +#define Q_FLAG +#endif + +#define SHORTOPTS "aAb" B_FLAG "c:C:d" D_FLAG "eE:fF:G:hHi:" I_FLAG j_FLAG J_FLAG "KlLm:M:nNOpq" Q_FLAG "r:s:StT:u" U_FLAG "vV:w:W:xXy:Yz:Z:#" + +/* + * Long options. + * + * We do not currently have long options corresponding to all short + * options; we should probably pick appropriate option names for them. + * + * However, the short options where the number of times the option is + * specified matters, such as -v and -d and -t, should probably not + * just map to a long option, as saying + * + * tcpdump --verbose --verbose + * + * doesn't make sense; it should be --verbosity={N} or something such + * as that. + * + * For long options with no corresponding short options, we define values + * outside the range of ASCII graphic characters, make that the last + * component of the entry for the long option, and have a case for that + * option in the switch statement. + */ +#define OPTION_VERSION 128 +#define OPTION_TSTAMP_PRECISION 129 +#define OPTION_IMMEDIATE_MODE 130 + +static const struct option longopts[] = { +#if defined(HAVE_PCAP_CREATE) || defined(_WIN32) + { "buffer-size", required_argument, NULL, 'B' }, +#endif + { "list-interfaces", no_argument, NULL, 'D' }, + { "help", no_argument, NULL, 'h' }, + { "interface", required_argument, NULL, 'i' }, +#ifdef HAVE_PCAP_CREATE + { "monitor-mode", no_argument, NULL, 'I' }, +#endif +#ifdef HAVE_PCAP_SET_TSTAMP_TYPE + { "time-stamp-type", required_argument, NULL, 'j' }, + { "list-time-stamp-types", no_argument, NULL, 'J' }, +#endif +#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION + { "time-stamp-precision", required_argument, NULL, OPTION_TSTAMP_PRECISION}, +#endif + { "dont-verify-checksums", no_argument, NULL, 'K' }, + { "list-data-link-types", no_argument, NULL, 'L' }, + { "no-optimize", no_argument, NULL, 'O' }, + { "no-promiscuous-mode", no_argument, NULL, 'p' }, +#ifdef HAVE_PCAP_SETDIRECTION + { "direction", required_argument, NULL, 'Q' }, +#endif + { "snapshot-length", required_argument, NULL, 's' }, + { "absolute-tcp-sequence-numbers", no_argument, NULL, 'S' }, +#ifdef HAVE_PCAP_DUMP_FLUSH + { "packet-buffered", no_argument, NULL, 'U' }, +#endif + { "linktype", required_argument, NULL, 'y' }, +#ifdef HAVE_PCAP_SET_IMMEDIATE_MODE + { "immediate-mode", no_argument, NULL, OPTION_IMMEDIATE_MODE }, +#endif +#ifdef HAVE_PCAP_SET_PARSER_DEBUG + { "debug-filter-parser", no_argument, NULL, 'Y' }, +#endif + { "relinquish-privileges", required_argument, NULL, 'Z' }, + { "number", no_argument, NULL, '#' }, + { "version", no_argument, NULL, OPTION_VERSION }, + { NULL, 0, NULL, 0 } +}; + +#ifndef _WIN32 +/* Drop root privileges and chroot if necessary */ +static void +droproot(const char *username, const char *chroot_dir) +{ + struct passwd *pw = NULL; + + if (chroot_dir && !username) { + fprintf(stderr, "%s: Chroot without dropping root is insecure\n", + program_name); + exit_tcpdump(1); + } + + pw = getpwnam(username); + if (pw) { + if (chroot_dir) { + if (chroot(chroot_dir) != 0 || chdir ("/") != 0) { + fprintf(stderr, "%s: Couldn't chroot/chdir to '%.64s': %s\n", + program_name, chroot_dir, pcap_strerror(errno)); + exit_tcpdump(1); + } + } +#ifdef HAVE_LIBCAP_NG + { + int ret = capng_change_id(pw->pw_uid, pw->pw_gid, CAPNG_NO_FLAG); + if (ret < 0) + error("capng_change_id(): return %d\n", ret); + else + fprintf(stderr, "dropped privs to %s\n", username); + } +#else + if (initgroups(pw->pw_name, pw->pw_gid) != 0 || + setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) { + fprintf(stderr, "%s: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n", + program_name, username, + (unsigned long)pw->pw_uid, + (unsigned long)pw->pw_gid, + pcap_strerror(errno)); + exit_tcpdump(1); + } + else { + fprintf(stderr, "dropped privs to %s\n", username); + } +#endif /* HAVE_LIBCAP_NG */ + } + else { + fprintf(stderr, "%s: Couldn't find user '%.32s'\n", + program_name, username); + exit_tcpdump(1); + } +#ifdef HAVE_LIBCAP_NG + /* We don't need CAP_SETUID, CAP_SETGID and CAP_SYS_CHROOT any more. */ + capng_updatev( + CAPNG_DROP, + CAPNG_EFFECTIVE | CAPNG_PERMITTED, + CAP_SETUID, + CAP_SETGID, + CAP_SYS_CHROOT, + -1); + capng_apply(CAPNG_SELECT_BOTH); +#endif /* HAVE_LIBCAP_NG */ + +} +#endif /* _WIN32 */ + +static int +getWflagChars(int x) +{ + int c = 0; + + x -= 1; + while (x > 0) { + c += 1; + x /= 10; + } + + return c; +} + + +static void +MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars) +{ + char *filename = malloc(PATH_MAX + 1); + if (filename == NULL) + error("Makefilename: malloc"); + + /* Process with strftime if Gflag is set. */ + if (Gflag != 0) { + struct tm *local_tm; + + /* Convert Gflag_time to a usable format */ + if ((local_tm = localtime(&Gflag_time)) == NULL) { + error("MakeTimedFilename: localtime"); + } + + /* There's no good way to detect an error in strftime since a return + * value of 0 isn't necessarily failure. + */ + strftime(filename, PATH_MAX, orig_name, local_tm); + } else { + strncpy(filename, orig_name, PATH_MAX); + } + + if (cnt == 0 && max_chars == 0) + strncpy(buffer, filename, PATH_MAX + 1); + else + if (snprintf(buffer, PATH_MAX + 1, "%s%0*d", filename, max_chars, cnt) > PATH_MAX) + /* Report an error if the filename is too large */ + error("too many output files or filename is too long (> %d)", PATH_MAX); + free(filename); +} + +static char * +get_next_file(FILE *VFile, char *ptr) +{ + char *ret; + size_t len; + + ret = fgets(ptr, PATH_MAX, VFile); + if (!ret) + return NULL; + + len = strlen (ptr); + if (len > 0 && ptr[len - 1] == '\n') + ptr[len - 1] = '\0'; + + return ret; +} + +#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION +static int +tstamp_precision_from_string(const char *precision) +{ + if (strncmp(precision, "nano", strlen("nano")) == 0) + return PCAP_TSTAMP_PRECISION_NANO; + + if (strncmp(precision, "micro", strlen("micro")) == 0) + return PCAP_TSTAMP_PRECISION_MICRO; + + return -EINVAL; +} + +static const char * +tstamp_precision_to_string(int precision) +{ + switch (precision) { + + case PCAP_TSTAMP_PRECISION_MICRO: + return "micro"; + + case PCAP_TSTAMP_PRECISION_NANO: + return "nano"; + + default: + return "unknown"; + } +} +#endif + +#ifdef HAVE_CAPSICUM +/* + * Ensure that, on a dump file's descriptor, we have all the rights + * necessary to make the standard I/O library work with an fdopen()ed + * FILE * from that descriptor. + * + * A long time ago, in a galaxy far far away, AT&T decided that, instead + * of providing separate APIs for getting and setting the FD_ flags on a + * descriptor, getting and setting the O_ flags on a descriptor, and + * locking files, they'd throw them all into a kitchen-sink fcntl() call + * along the lines of ioctl(), the fact that ioctl() operations are + * largely specific to particular character devices but fcntl() operations + * are either generic to all descriptors or generic to all descriptors for + * regular files nonwithstanding. + * + * The Capsicum people decided that fine-grained control of descriptor + * operations was required, so that you need to grant permission for + * reading, writing, seeking, and fcntl-ing. The latter, courtesy of + * AT&T's decision, means that "fcntl-ing" isn't a thing, but a motley + * collection of things, so there are *individual* fcntls for which + * permission needs to be granted. + * + * The FreeBSD standard I/O people implemented some optimizations that + * requires that the standard I/O routines be able to determine whether + * the descriptor for the FILE * is open append-only or not; as that + * descriptor could have come from an open() rather than an fopen(), + * that requires that it be able to do an F_GETFL fcntl() to read + * the O_ flags. + * + * Tcpdump uses ftell() to determine how much data has been written + * to a file in order to, when used with -C, determine when it's time + * to rotate capture files. ftell() therefore needs to do an lseek() + * to find out the file offset and must, thanks to the aforementioned + * optimization, also know whether the descriptor is open append-only + * or not. + * + * The net result of all the above is that we need to grant CAP_SEEK, + * CAP_WRITE, and CAP_FCNTL with the CAP_FCNTL_GETFL subcapability. + * + * Perhaps this is the universe's way of saying that either + * + * 1) there needs to be an fopenat() call and a pcap_dump_openat() call + * using it, so that Capsicum-capable tcpdump wouldn't need to do + * an fdopen() + * + * or + * + * 2) there needs to be a cap_fdopen() call in the FreeBSD standard + * I/O library that knows what rights are needed by the standard + * I/O library, based on the open mode, and assigns them, perhaps + * with an additional argument indicating, for example, whether + * seeking should be allowed, so that tcpdump doesn't need to know + * what the standard I/O library happens to require this week. + */ +static void +set_dumper_capsicum_rights(pcap_dumper_t *p) +{ + int fd = fileno(pcap_dump_file(p)); + cap_rights_t rights; + + cap_rights_init(&rights, CAP_SEEK, CAP_WRITE, CAP_FCNTL); + if (cap_rights_limit(fd, &rights) < 0 && errno != ENOSYS) { + error("unable to limit dump descriptor"); + } + if (cap_fcntls_limit(fd, CAP_FCNTL_GETFL) < 0 && errno != ENOSYS) { + error("unable to limit dump descriptor fcntls"); + } +} +#endif + +/* + * Copy arg vector into a new buffer, concatenating arguments with spaces. + */ +static char * +copy_argv(register char **argv) +{ + register char **p; + register u_int len = 0; + char *buf; + char *src, *dst; + + p = argv; + if (*p == NULL) + return 0; + + while (*p) + len += strlen(*p++) + 1; + + buf = (char *)malloc(len); + if (buf == NULL) + error("copy_argv: malloc"); + + p = argv; + dst = buf; + while ((src = *p++) != NULL) { + while ((*dst++ = *src++) != '\0') + ; + dst[-1] = ' '; + } + dst[-1] = '\0'; + + return buf; +} + +/* + * On Windows, we need to open the file in binary mode, so that + * we get all the bytes specified by the size we get from "fstat()". + * On UNIX, that's not necessary. O_BINARY is defined on Windows; + * we define it as 0 if it's not defined, so it does nothing. + */ +#ifndef O_BINARY +#define O_BINARY 0 +#endif + +static char * +read_infile(char *fname) +{ + register int i, fd, cc; + register char *cp; + struct stat buf; + + fd = open(fname, O_RDONLY|O_BINARY); + if (fd < 0) + error("can't open %s: %s", fname, pcap_strerror(errno)); + + if (fstat(fd, &buf) < 0) + error("can't stat %s: %s", fname, pcap_strerror(errno)); + + cp = malloc((u_int)buf.st_size + 1); + if (cp == NULL) + error("malloc(%d) for %s: %s", (u_int)buf.st_size + 1, + fname, pcap_strerror(errno)); + cc = read(fd, cp, (u_int)buf.st_size); + if (cc < 0) + error("read %s: %s", fname, pcap_strerror(errno)); + if (cc != buf.st_size) + error("short read %s (%d != %d)", fname, cc, (int)buf.st_size); + + close(fd); + /* replace "# comment" with spaces */ + for (i = 0; i < cc; i++) { + if (cp[i] == '#') + while (i < cc && cp[i] != '\n') + cp[i++] = ' '; + } + cp[cc] = '\0'; + return (cp); +} + +#ifdef HAVE_PCAP_FINDALLDEVS +static long +parse_interface_number(const char *device) +{ + long devnum; + char *end; + + devnum = strtol(device, &end, 10); + if (device != end && *end == '\0') { + /* + * It's all-numeric, but is it a valid number? + */ + if (devnum <= 0) { + /* + * No, it's not an ordinal. + */ + error("Invalid adapter index"); + } + return (devnum); + } else { + /* + * It's not all-numeric; return -1, so our caller + * knows that. + */ + return (-1); + } +} + +static char * +find_interface_by_number(long devnum) +{ + pcap_if_t *dev, *devlist; + long i; + char ebuf[PCAP_ERRBUF_SIZE]; + char *device; + + if (pcap_findalldevs(&devlist, ebuf) < 0) + error("%s", ebuf); + /* + * Look for the devnum-th entry in the list of devices (1-based). + */ + for (i = 0, dev = devlist; i < devnum-1 && dev != NULL; + i++, dev = dev->next) + ; + if (dev == NULL) + error("Invalid adapter index"); + device = strdup(dev->name); + pcap_freealldevs(devlist); + return (device); +} +#endif + +static pcap_t * +open_interface(const char *device, netdissect_options *ndo, char *ebuf) +{ + pcap_t *pc; +#ifdef HAVE_PCAP_CREATE + int status; + char *cp; +#endif + +#ifdef HAVE_PCAP_CREATE + pc = pcap_create(device, ebuf); + if (pc == NULL) { + /* + * If this failed with "No such device", that means + * the interface doesn't exist; return NULL, so that + * the caller can see whether the device name is + * actually an interface index. + */ + if (strstr(ebuf, "No such device") != NULL) + return (NULL); + error("%s", ebuf); + } +#ifdef HAVE_PCAP_SET_TSTAMP_TYPE + if (Jflag) + show_tstamp_types_and_exit(pc, device); +#endif +#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION + status = pcap_set_tstamp_precision(pc, ndo->ndo_tstamp_precision); + if (status != 0) + error("%s: Can't set %ssecond time stamp precision: %s", + device, + tstamp_precision_to_string(ndo->ndo_tstamp_precision), + pcap_statustostr(status)); +#endif + +#ifdef HAVE_PCAP_SET_IMMEDIATE_MODE + if (immediate_mode) { + status = pcap_set_immediate_mode(pc, 1); + if (status != 0) + error("%s: Can't set immediate mode: %s", + device, + pcap_statustostr(status)); + } +#endif + /* + * Is this an interface that supports monitor mode? + */ + if (pcap_can_set_rfmon(pc) == 1) + supports_monitor_mode = 1; + else + supports_monitor_mode = 0; + status = pcap_set_snaplen(pc, ndo->ndo_snaplen); + if (status != 0) + error("%s: Can't set snapshot length: %s", + device, pcap_statustostr(status)); + status = pcap_set_promisc(pc, !pflag); + if (status != 0) + error("%s: Can't set promiscuous mode: %s", + device, pcap_statustostr(status)); + if (Iflag) { + status = pcap_set_rfmon(pc, 1); + if (status != 0) + error("%s: Can't set monitor mode: %s", + device, pcap_statustostr(status)); + } + status = pcap_set_timeout(pc, 1000); + if (status != 0) + error("%s: pcap_set_timeout failed: %s", + device, pcap_statustostr(status)); + if (Bflag != 0) { + status = pcap_set_buffer_size(pc, Bflag); + if (status != 0) + error("%s: Can't set buffer size: %s", + device, pcap_statustostr(status)); + } +#ifdef HAVE_PCAP_SET_TSTAMP_TYPE + if (jflag != -1) { + status = pcap_set_tstamp_type(pc, jflag); + if (status < 0) + error("%s: Can't set time stamp type: %s", + device, pcap_statustostr(status)); + else if (status > 0) + warning("When trying to set timestamp type '%s' on %s: %s", + pcap_tstamp_type_val_to_name(jflag), device, + pcap_statustostr(status)); + } +#endif + status = pcap_activate(pc); + if (status < 0) { + /* + * pcap_activate() failed. + */ + cp = pcap_geterr(pc); + if (status == PCAP_ERROR) + error("%s", cp); + else if (status == PCAP_ERROR_NO_SUCH_DEVICE) { + /* + * Return an error for our caller to handle. + */ + snprintf(ebuf, PCAP_ERRBUF_SIZE, "%s: %s\n(%s)", + device, pcap_statustostr(status), cp); + pcap_close(pc); + return (NULL); + } else if (status == PCAP_ERROR_PERM_DENIED && *cp != '\0') + error("%s: %s\n(%s)", device, + pcap_statustostr(status), cp); + else + error("%s: %s", device, + pcap_statustostr(status)); + } else if (status > 0) { + /* + * pcap_activate() succeeded, but it's warning us + * of a problem it had. + */ + cp = pcap_geterr(pc); + if (status == PCAP_WARNING) + warning("%s", cp); + else if (status == PCAP_WARNING_PROMISC_NOTSUP && + *cp != '\0') + warning("%s: %s\n(%s)", device, + pcap_statustostr(status), cp); + else + warning("%s: %s", device, + pcap_statustostr(status)); + } +#ifdef HAVE_PCAP_SETDIRECTION + if (Qflag != -1) { + status = pcap_setdirection(pc, Qflag); + if (status != 0) + error("%s: pcap_setdirection() failed: %s", + device, pcap_geterr(pc)); + } +#endif /* HAVE_PCAP_SETDIRECTION */ +#else /* HAVE_PCAP_CREATE */ + *ebuf = '\0'; + pc = pcap_open_live(device, ndo->ndo_snaplen, !pflag, 1000, ebuf); + if (pc == NULL) { + /* + * If this failed with "No such device", that means + * the interface doesn't exist; return NULL, so that + * the caller can see whether the device name is + * actually an interface index. + */ + if (strstr(ebuf, "No such device") != NULL) + return (NULL); + error("%s", ebuf); + } + if (*ebuf) + warning("%s", ebuf); +#endif /* HAVE_PCAP_CREATE */ + + return (pc); +} + +int +main(int argc, char **argv) +{ + register int cnt, op, i; + bpf_u_int32 localnet =0 , netmask = 0; + int timezone_offset = 0; + register char *cp, *infile, *cmdbuf, *device, *RFileName, *VFileName, *WFileName; + pcap_handler callback; + int dlt; + const char *dlt_name; + struct bpf_program fcode; +#ifndef _WIN32 + RETSIGTYPE (*oldhandler)(int); +#endif + struct dump_info dumpinfo; + u_char *pcap_userdata; + char ebuf[PCAP_ERRBUF_SIZE]; + char VFileLine[PATH_MAX + 1]; + char *username = NULL; + char *chroot_dir = NULL; + char *ret = NULL; + char *end; +#ifdef HAVE_PCAP_FINDALLDEVS + pcap_if_t *devlist; + long devnum; +#endif + int status; + FILE *VFile; +#ifdef HAVE_CAPSICUM + cap_rights_t rights; + int cansandbox; +#endif /* HAVE_CAPSICUM */ + int Oflag = 1; /* run filter code optimizer */ + int yflag_dlt = -1; + const char *yflag_dlt_name = NULL; + + netdissect_options Ndo; + netdissect_options *ndo = &Ndo; + + /* + * Initialize the netdissect code. + */ + if (nd_init(ebuf, sizeof ebuf) == -1) + error("%s", ebuf); + + memset(ndo, 0, sizeof(*ndo)); + ndo_set_function_pointers(ndo); + ndo->ndo_snaplen = DEFAULT_SNAPLEN; + + cnt = -1; + device = NULL; + infile = NULL; + RFileName = NULL; + VFileName = NULL; + VFile = NULL; + WFileName = NULL; + dlt = -1; + if ((cp = strrchr(argv[0], '/')) != NULL) + ndo->program_name = program_name = cp + 1; + else + ndo->program_name = program_name = argv[0]; + +#ifdef _WIN32 + if (pcap_wsockinit() != 0) + error("Attempting to initialize Winsock failed"); +#endif /* _WIN32 */ + + /* + * On platforms where the CPU doesn't support unaligned loads, + * force unaligned accesses to abort with SIGBUS, rather than + * being fixed up (slowly) by the OS kernel; on those platforms, + * misaligned accesses are bugs, and we want tcpdump to crash so + * that the bugs are reported. + */ + if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0) + error("%s", ebuf); + + while ( + (op = getopt_long(argc, argv, SHORTOPTS, longopts, NULL)) != -1) + switch (op) { + + case 'a': + /* compatibility for old -a */ + break; + + case 'A': + ++ndo->ndo_Aflag; + break; + + case 'b': + ++ndo->ndo_bflag; + break; + +#if defined(HAVE_PCAP_CREATE) || defined(_WIN32) + case 'B': + Bflag = atoi(optarg)*1024; + if (Bflag <= 0) + error("invalid packet buffer size %s", optarg); + break; +#endif /* defined(HAVE_PCAP_CREATE) || defined(_WIN32) */ + + case 'c': + cnt = atoi(optarg); + if (cnt <= 0) + error("invalid packet count %s", optarg); + break; + + case 'C': + Cflag = atoi(optarg) * 1000000; + if (Cflag <= 0) + error("invalid file size %s", optarg); + break; + + case 'd': + ++dflag; + break; + + case 'D': + Dflag++; + break; + + case 'L': + Lflag++; + break; + + case 'e': + ++ndo->ndo_eflag; + break; + + case 'E': +#ifndef HAVE_LIBCRYPTO + warning("crypto code not compiled in"); +#endif + ndo->ndo_espsecret = optarg; + break; + + case 'f': + ++ndo->ndo_fflag; + break; + + case 'F': + infile = optarg; + break; + + case 'G': + Gflag = atoi(optarg); + if (Gflag < 0) + error("invalid number of seconds %s", optarg); + + /* We will create one file initially. */ + Gflag_count = 0; + + /* Grab the current time for rotation use. */ + if ((Gflag_time = time(NULL)) == (time_t)-1) { + error("main: can't get current time: %s", + pcap_strerror(errno)); + } + break; + + case 'h': + print_usage(); + exit_tcpdump(0); + break; + + case 'H': + ++ndo->ndo_Hflag; + break; + + case 'i': + device = optarg; + break; + +#ifdef HAVE_PCAP_CREATE + case 'I': + ++Iflag; + break; +#endif /* HAVE_PCAP_CREATE */ + +#ifdef HAVE_PCAP_SET_TSTAMP_TYPE + case 'j': + jflag = pcap_tstamp_type_name_to_val(optarg); + if (jflag < 0) + error("invalid time stamp type %s", optarg); + break; + + case 'J': + Jflag++; + break; +#endif + + case 'l': +#ifdef _WIN32 + /* + * _IOLBF is the same as _IOFBF in Microsoft's C + * libraries; the only alternative they offer + * is _IONBF. + * + * XXX - this should really be checking for MSVC++, + * not _WIN32, if, for example, MinGW has its own + * C library that is more UNIX-compatible. + */ + setvbuf(stdout, NULL, _IONBF, 0); +#else /* _WIN32 */ +#ifdef HAVE_SETLINEBUF + setlinebuf(stdout); +#else + setvbuf(stdout, NULL, _IOLBF, 0); +#endif +#endif /* _WIN32 */ + break; + + case 'K': + ++ndo->ndo_Kflag; + break; + + case 'm': + if (nd_have_smi_support()) { + if (nd_load_smi_module(optarg, ebuf, sizeof ebuf) == -1) + error("%s", ebuf); + } else { + (void)fprintf(stderr, "%s: ignoring option `-m %s' ", + program_name, optarg); + (void)fprintf(stderr, "(no libsmi support)\n"); + } + break; + + case 'M': + /* TCP-MD5 shared secret */ +#ifndef HAVE_LIBCRYPTO + warning("crypto code not compiled in"); +#endif + ndo->ndo_sigsecret = optarg; + break; + + case 'n': + ++ndo->ndo_nflag; + break; + + case 'N': + ++ndo->ndo_Nflag; + break; + + case 'O': + Oflag = 0; + break; + + case 'p': + ++pflag; + break; + + case 'q': + ++ndo->ndo_qflag; + ++ndo->ndo_suppress_default_print; + break; + +#ifdef HAVE_PCAP_SETDIRECTION + case 'Q': + if (ascii_strcasecmp(optarg, "in") == 0) + Qflag = PCAP_D_IN; + else if (ascii_strcasecmp(optarg, "out") == 0) + Qflag = PCAP_D_OUT; + else if (ascii_strcasecmp(optarg, "inout") == 0) + Qflag = PCAP_D_INOUT; + else + error("unknown capture direction `%s'", optarg); + break; +#endif /* HAVE_PCAP_SETDIRECTION */ + + case 'r': + RFileName = optarg; + break; + + case 's': + ndo->ndo_snaplen = strtol(optarg, &end, 0); + if (optarg == end || *end != '\0' + || ndo->ndo_snaplen < 0 || ndo->ndo_snaplen > MAXIMUM_SNAPLEN) + error("invalid snaplen %s", optarg); + else if (ndo->ndo_snaplen == 0) + ndo->ndo_snaplen = MAXIMUM_SNAPLEN; + break; + + case 'S': + ++ndo->ndo_Sflag; + break; + + case 't': + ++ndo->ndo_tflag; + break; + + case 'T': + if (ascii_strcasecmp(optarg, "vat") == 0) + ndo->ndo_packettype = PT_VAT; + else if (ascii_strcasecmp(optarg, "wb") == 0) + ndo->ndo_packettype = PT_WB; + else if (ascii_strcasecmp(optarg, "rpc") == 0) + ndo->ndo_packettype = PT_RPC; + else if (ascii_strcasecmp(optarg, "rtp") == 0) + ndo->ndo_packettype = PT_RTP; + else if (ascii_strcasecmp(optarg, "rtcp") == 0) + ndo->ndo_packettype = PT_RTCP; + else if (ascii_strcasecmp(optarg, "snmp") == 0) + ndo->ndo_packettype = PT_SNMP; + else if (ascii_strcasecmp(optarg, "cnfp") == 0) + ndo->ndo_packettype = PT_CNFP; + else if (ascii_strcasecmp(optarg, "tftp") == 0) + ndo->ndo_packettype = PT_TFTP; + else if (ascii_strcasecmp(optarg, "aodv") == 0) + ndo->ndo_packettype = PT_AODV; + else if (ascii_strcasecmp(optarg, "carp") == 0) + ndo->ndo_packettype = PT_CARP; + else if (ascii_strcasecmp(optarg, "radius") == 0) + ndo->ndo_packettype = PT_RADIUS; + else if (ascii_strcasecmp(optarg, "zmtp1") == 0) + ndo->ndo_packettype = PT_ZMTP1; + else if (ascii_strcasecmp(optarg, "vxlan") == 0) + ndo->ndo_packettype = PT_VXLAN; + else if (ascii_strcasecmp(optarg, "pgm") == 0) + ndo->ndo_packettype = PT_PGM; + else if (ascii_strcasecmp(optarg, "pgm_zmtp1") == 0) + ndo->ndo_packettype = PT_PGM_ZMTP1; + else if (ascii_strcasecmp(optarg, "lmp") == 0) + ndo->ndo_packettype = PT_LMP; + else if (ascii_strcasecmp(optarg, "resp") == 0) + ndo->ndo_packettype = PT_RESP; + else + error("unknown packet type `%s'", optarg); + break; + + case 'u': + ++ndo->ndo_uflag; + break; + +#ifdef HAVE_PCAP_DUMP_FLUSH + case 'U': + ++Uflag; + break; +#endif + + case 'v': + ++ndo->ndo_vflag; + break; + + case 'V': + VFileName = optarg; + break; + + case 'w': + WFileName = optarg; + break; + + case 'W': + Wflag = atoi(optarg); + if (Wflag <= 0) + error("invalid number of output files %s", optarg); + WflagChars = getWflagChars(Wflag); + break; + + case 'x': + ++ndo->ndo_xflag; + ++ndo->ndo_suppress_default_print; + break; + + case 'X': + ++ndo->ndo_Xflag; + ++ndo->ndo_suppress_default_print; + break; + + case 'y': + yflag_dlt_name = optarg; + yflag_dlt = + pcap_datalink_name_to_val(yflag_dlt_name); + if (yflag_dlt < 0) + error("invalid data link type %s", yflag_dlt_name); + break; + +#ifdef HAVE_PCAP_SET_PARSER_DEBUG + case 'Y': + { + /* Undocumented flag */ + pcap_set_parser_debug(1); + } + break; +#endif + case 'z': + zflag = optarg; + break; + + case 'Z': + username = optarg; + break; + + case '#': + ndo->ndo_packet_number = 1; + break; + + case OPTION_VERSION: + print_version(); + exit_tcpdump(0); + break; + +#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION + case OPTION_TSTAMP_PRECISION: + ndo->ndo_tstamp_precision = tstamp_precision_from_string(optarg); + if (ndo->ndo_tstamp_precision < 0) + error("unsupported time stamp precision"); + break; +#endif + +#ifdef HAVE_PCAP_SET_IMMEDIATE_MODE + case OPTION_IMMEDIATE_MODE: + immediate_mode = 1; + break; +#endif + + default: + print_usage(); + exit_tcpdump(1); + /* NOTREACHED */ + } + +#ifdef HAVE_PCAP_FINDALLDEVS + if (Dflag) + show_devices_and_exit(); +#endif + + switch (ndo->ndo_tflag) { + + case 0: /* Default */ + case 4: /* Default + Date*/ + timezone_offset = gmt2local(0); + break; + + case 1: /* No time stamp */ + case 2: /* Unix timeval style */ + case 3: /* Microseconds since previous packet */ + case 5: /* Microseconds since first packet */ + break; + + default: /* Not supported */ + error("only -t, -tt, -ttt, -tttt and -ttttt are supported"); + break; + } + + if (ndo->ndo_fflag != 0 && (VFileName != NULL || RFileName != NULL)) + error("-f can not be used with -V or -r"); + + if (VFileName != NULL && RFileName != NULL) + error("-V and -r are mutually exclusive."); + +#ifdef HAVE_PCAP_SET_IMMEDIATE_MODE + /* + * If we're printing dissected packets to the standard output + * rather than saving raw packets to a file, and the standard + * output is a terminal, use immediate mode, as the user's + * probably expecting to see packets pop up immediately. + */ + if (WFileName == NULL && isatty(1)) + immediate_mode = 1; +#endif + +#ifdef WITH_CHROOT + /* if run as root, prepare for chrooting */ + if (getuid() == 0 || geteuid() == 0) { + /* future extensibility for cmd-line arguments */ + if (!chroot_dir) + chroot_dir = WITH_CHROOT; + } +#endif + +#ifdef WITH_USER + /* if run as root, prepare for dropping root privileges */ + if (getuid() == 0 || geteuid() == 0) { + /* Run with '-Z root' to restore old behaviour */ + if (!username) + username = WITH_USER; + } +#endif + + if (RFileName != NULL || VFileName != NULL) { + /* + * If RFileName is non-null, it's the pathname of a + * savefile to read. If VFileName is non-null, it's + * the pathname of a file containing a list of pathnames + * (one per line) of savefiles to read. + * + * In either case, we're reading a savefile, not doing + * a live capture. + */ +#ifndef _WIN32 + /* + * We don't need network access, so relinquish any set-UID + * or set-GID privileges we have (if any). + * + * We do *not* want set-UID privileges when opening a + * trace file, as that might let the user read other + * people's trace files (especially if we're set-UID + * root). + */ + if (setgid(getgid()) != 0 || setuid(getuid()) != 0 ) + fprintf(stderr, "Warning: setgid/setuid failed !\n"); +#endif /* _WIN32 */ + if (VFileName != NULL) { + if (VFileName[0] == '-' && VFileName[1] == '\0') + VFile = stdin; + else + VFile = fopen(VFileName, "r"); + + if (VFile == NULL) + error("Unable to open file: %s\n", pcap_strerror(errno)); + + ret = get_next_file(VFile, VFileLine); + if (!ret) + error("Nothing in %s\n", VFileName); + RFileName = VFileLine; + } + +#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION + pd = pcap_open_offline_with_tstamp_precision(RFileName, + ndo->ndo_tstamp_precision, ebuf); +#else + pd = pcap_open_offline(RFileName, ebuf); +#endif + + if (pd == NULL) + error("%s", ebuf); +#ifdef HAVE_CAPSICUM + cap_rights_init(&rights, CAP_READ); + if (cap_rights_limit(fileno(pcap_file(pd)), &rights) < 0 && + errno != ENOSYS) { + error("unable to limit pcap descriptor"); + } +#endif + dlt = pcap_datalink(pd); + dlt_name = pcap_datalink_val_to_name(dlt); + if (dlt_name == NULL) { + fprintf(stderr, "reading from file %s, link-type %u\n", + RFileName, dlt); + } else { + fprintf(stderr, + "reading from file %s, link-type %s (%s)\n", + RFileName, dlt_name, + pcap_datalink_val_to_description(dlt)); + } + } else { + /* + * We're doing a live capture. + */ + if (device == NULL) { + /* + * No interface was specified. Pick one. + */ +#ifdef HAVE_PCAP_FINDALLDEVS + /* + * Find the list of interfaces, and pick + * the first interface. + */ + if (pcap_findalldevs(&devlist, ebuf) >= 0 && + devlist != NULL) { + device = strdup(devlist->name); + pcap_freealldevs(devlist); + } +#else /* HAVE_PCAP_FINDALLDEVS */ + /* + * Use whatever interface pcap_lookupdev() + * chooses. + */ + device = pcap_lookupdev(ebuf); +#endif + if (device == NULL) + error("%s", ebuf); + } + + /* + * Try to open the interface with the specified name. + */ + pd = open_interface(device, ndo, ebuf); + if (pd == NULL) { + /* + * That failed. If we can get a list of + * interfaces, and the interface name + * is purely numeric, try to use it as + * a 1-based index in the list of + * interfaces. + */ +#ifdef HAVE_PCAP_FINDALLDEVS + devnum = parse_interface_number(device); + if (devnum == -1) { + /* + * It's not a number; just report + * the open error and fail. + */ + error("%s", ebuf); + } + + /* + * OK, it's a number; try to find the + * interface with that index, and try + * to open it. + * + * find_interface_by_number() exits if it + * couldn't be found. + */ + device = find_interface_by_number(devnum); + pd = open_interface(device, ndo, ebuf); + if (pd == NULL) + error("%s", ebuf); +#else /* HAVE_PCAP_FINDALLDEVS */ + /* + * We can't get a list of interfaces; just + * fail. + */ + error("%s", ebuf); +#endif /* HAVE_PCAP_FINDALLDEVS */ + } + + /* + * Let user own process after socket has been opened. + */ +#ifndef _WIN32 + if (setgid(getgid()) != 0 || setuid(getuid()) != 0) + fprintf(stderr, "Warning: setgid/setuid failed !\n"); +#endif /* _WIN32 */ +#if !defined(HAVE_PCAP_CREATE) && defined(_WIN32) + if(Bflag != 0) + if(pcap_setbuff(pd, Bflag)==-1){ + error("%s", pcap_geterr(pd)); + } +#endif /* !defined(HAVE_PCAP_CREATE) && defined(_WIN32) */ + if (Lflag) + show_dlts_and_exit(pd, device); + if (yflag_dlt >= 0) { +#ifdef HAVE_PCAP_SET_DATALINK + if (pcap_set_datalink(pd, yflag_dlt) < 0) + error("%s", pcap_geterr(pd)); +#else + /* + * We don't actually support changing the + * data link type, so we only let them + * set it to what it already is. + */ + if (yflag_dlt != pcap_datalink(pd)) { + error("%s is not one of the DLTs supported by this device\n", + yflag_dlt_name); + } +#endif + (void)fprintf(stderr, "%s: data link type %s\n", + program_name, yflag_dlt_name); + (void)fflush(stderr); + } + i = pcap_snapshot(pd); + if (ndo->ndo_snaplen < i) { + warning("snaplen raised from %d to %d", ndo->ndo_snaplen, i); + ndo->ndo_snaplen = i; + } + if(ndo->ndo_fflag != 0) { + if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) { + warning("foreign (-f) flag used but: %s", ebuf); + } + } + + } + if (infile) + cmdbuf = read_infile(infile); + else + cmdbuf = copy_argv(&argv[optind]); + +#ifdef HAVE_PCAP_SET_OPTIMIZER_DEBUG + pcap_set_optimizer_debug(dflag); +#endif + if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0) + error("%s", pcap_geterr(pd)); + if (dflag) { + bpf_dump(&fcode, dflag); + pcap_close(pd); + free(cmdbuf); + pcap_freecode(&fcode); + exit_tcpdump(0); + } + init_print(ndo, localnet, netmask, timezone_offset); + +#ifndef _WIN32 + (void)setsignal(SIGPIPE, cleanup); + (void)setsignal(SIGTERM, cleanup); + (void)setsignal(SIGINT, cleanup); +#endif /* _WIN32 */ +#if defined(HAVE_FORK) || defined(HAVE_VFORK) + (void)setsignal(SIGCHLD, child_cleanup); +#endif + /* Cooperate with nohup(1) */ +#ifndef _WIN32 + if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL) + (void)setsignal(SIGHUP, oldhandler); +#endif /* _WIN32 */ + +#ifndef _WIN32 + /* + * If a user name was specified with "-Z", attempt to switch to + * that user's UID. This would probably be used with sudo, + * to allow tcpdump to be run in a special restricted + * account (if you just want to allow users to open capture + * devices, and can't just give users that permission, + * you'd make tcpdump set-UID or set-GID). + * + * Tcpdump doesn't necessarily write only to one savefile; + * the general only way to allow a -Z instance to write to + * savefiles as the user under whose UID it's run, rather + * than as the user specified with -Z, would thus be to switch + * to the original user ID before opening a capture file and + * then switch back to the -Z user ID after opening the savefile. + * Switching to the -Z user ID only after opening the first + * savefile doesn't handle the general case. + */ + + if (getuid() == 0 || geteuid() == 0) { +#ifdef HAVE_LIBCAP_NG + /* Initialize capng */ + capng_clear(CAPNG_SELECT_BOTH); + if (username) { + capng_updatev( + CAPNG_ADD, + CAPNG_PERMITTED | CAPNG_EFFECTIVE, + CAP_SETUID, + CAP_SETGID, + -1); + } + if (chroot_dir) { + capng_update( + CAPNG_ADD, + CAPNG_PERMITTED | CAPNG_EFFECTIVE, + CAP_SYS_CHROOT + ); + } + + if (WFileName) { + capng_update( + CAPNG_ADD, + CAPNG_PERMITTED | CAPNG_EFFECTIVE, + CAP_DAC_OVERRIDE + ); + } + capng_apply(CAPNG_SELECT_BOTH); +#endif /* HAVE_LIBCAP_NG */ + if (username || chroot_dir) + droproot(username, chroot_dir); + + } +#endif /* _WIN32 */ + + if (pcap_setfilter(pd, &fcode) < 0) + error("%s", pcap_geterr(pd)); +#ifdef HAVE_CAPSICUM + if (RFileName == NULL && VFileName == NULL) { + static const unsigned long cmds[] = { BIOCGSTATS, BIOCROTZBUF }; + + /* + * The various libpcap devices use a combination of + * read (bpf), ioctl (bpf, netmap), poll (netmap) + * so we add the relevant access rights. + */ + cap_rights_init(&rights, CAP_IOCTL, CAP_READ, CAP_EVENT); + if (cap_rights_limit(pcap_fileno(pd), &rights) < 0 && + errno != ENOSYS) { + error("unable to limit pcap descriptor"); + } + if (cap_ioctls_limit(pcap_fileno(pd), cmds, + sizeof(cmds) / sizeof(cmds[0])) < 0 && errno != ENOSYS) { + error("unable to limit ioctls on pcap descriptor"); + } + } +#endif + if (WFileName) { + pcap_dumper_t *p; + /* Do not exceed the default PATH_MAX for files. */ + dumpinfo.CurrentFileName = (char *)malloc(PATH_MAX + 1); + + if (dumpinfo.CurrentFileName == NULL) + error("malloc of dumpinfo.CurrentFileName"); + + /* We do not need numbering for dumpfiles if Cflag isn't set. */ + if (Cflag != 0) + MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, WflagChars); + else + MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, 0); + + p = pcap_dump_open(pd, dumpinfo.CurrentFileName); +#ifdef HAVE_LIBCAP_NG + /* Give up CAP_DAC_OVERRIDE capability. + * Only allow it to be restored if the -C or -G flag have been + * set since we may need to create more files later on. + */ + capng_update( + CAPNG_DROP, + (Cflag || Gflag ? 0 : CAPNG_PERMITTED) + | CAPNG_EFFECTIVE, + CAP_DAC_OVERRIDE + ); + capng_apply(CAPNG_SELECT_BOTH); +#endif /* HAVE_LIBCAP_NG */ + if (p == NULL) + error("%s", pcap_geterr(pd)); +#ifdef HAVE_CAPSICUM + set_dumper_capsicum_rights(p); +#endif + if (Cflag != 0 || Gflag != 0) { +#ifdef HAVE_CAPSICUM + dumpinfo.WFileName = strdup(basename(WFileName)); + if (dumpinfo.WFileName == NULL) { + error("Unable to allocate memory for file %s", + WFileName); + } + dumpinfo.dirfd = open(dirname(WFileName), + O_DIRECTORY | O_RDONLY); + if (dumpinfo.dirfd < 0) { + error("unable to open directory %s", + dirname(WFileName)); + } + cap_rights_init(&rights, CAP_CREATE, CAP_FCNTL, + CAP_FTRUNCATE, CAP_LOOKUP, CAP_SEEK, CAP_WRITE); + if (cap_rights_limit(dumpinfo.dirfd, &rights) < 0 && + errno != ENOSYS) { + error("unable to limit directory rights"); + } + if (cap_fcntls_limit(dumpinfo.dirfd, CAP_FCNTL_GETFL) < 0 && + errno != ENOSYS) { + error("unable to limit dump descriptor fcntls"); + } +#else /* !HAVE_CAPSICUM */ + dumpinfo.WFileName = WFileName; +#endif + callback = dump_packet_and_trunc; + dumpinfo.pd = pd; + dumpinfo.p = p; + pcap_userdata = (u_char *)&dumpinfo; + } else { + callback = dump_packet; + pcap_userdata = (u_char *)p; + } +#ifdef HAVE_PCAP_DUMP_FLUSH + if (Uflag) + pcap_dump_flush(p); +#endif + } else { + dlt = pcap_datalink(pd); + ndo->ndo_if_printer = get_if_printer(ndo, dlt); + callback = print_packet; + pcap_userdata = (u_char *)ndo; + } + +#ifdef SIGNAL_REQ_INFO + /* + * We can't get statistics when reading from a file rather + * than capturing from a device. + */ + if (RFileName == NULL) + (void)setsignal(SIGNAL_REQ_INFO, requestinfo); +#endif + + if (ndo->ndo_vflag > 0 && WFileName) { + /* + * When capturing to a file, "-v" means tcpdump should, + * every 10 seconds, "v"erbosely report the number of + * packets captured. + */ +#ifdef USE_WIN32_MM_TIMER + /* call verbose_stats_dump() each 1000 +/-100msec */ + timer_id = timeSetEvent(1000, 100, verbose_stats_dump, 0, TIME_PERIODIC); + setvbuf(stderr, NULL, _IONBF, 0); +#elif defined(HAVE_ALARM) + (void)setsignal(SIGALRM, verbose_stats_dump); + alarm(1); +#endif + } + + if (RFileName == NULL) { + /* + * Live capture (if -V was specified, we set RFileName + * to a file from the -V file). Print a message to + * the standard error on UN*X. + */ + if (!ndo->ndo_vflag && !WFileName) { + (void)fprintf(stderr, + "%s: verbose output suppressed, use -v or -vv for full protocol decode\n", + program_name); + } else + (void)fprintf(stderr, "%s: ", program_name); + dlt = pcap_datalink(pd); + dlt_name = pcap_datalink_val_to_name(dlt); + if (dlt_name == NULL) { + (void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n", + device, dlt, ndo->ndo_snaplen); + } else { + (void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n", + device, dlt_name, + pcap_datalink_val_to_description(dlt), ndo->ndo_snaplen); + } + (void)fflush(stderr); + } + +#ifdef HAVE_CAPSICUM + cansandbox = (ndo->ndo_nflag && VFileName == NULL && zflag == NULL); + if (cansandbox && cap_enter() < 0 && errno != ENOSYS) + error("unable to enter the capability mode"); +#endif /* HAVE_CAPSICUM */ + + do { + status = pcap_loop(pd, cnt, callback, pcap_userdata); + if (WFileName == NULL) { + /* + * We're printing packets. Flush the printed output, + * so it doesn't get intermingled with error output. + */ + if (status == -2) { + /* + * We got interrupted, so perhaps we didn't + * manage to finish a line we were printing. + * Print an extra newline, just in case. + */ + putchar('\n'); + } + (void)fflush(stdout); + } + if (status == -2) { + /* + * We got interrupted. If we are reading multiple + * files (via -V) set these so that we stop. + */ + VFileName = NULL; + ret = NULL; + } + if (status == -1) { + /* + * Error. Report it. + */ + (void)fprintf(stderr, "%s: pcap_loop: %s\n", + program_name, pcap_geterr(pd)); + } + if (RFileName == NULL) { + /* + * We're doing a live capture. Report the capture + * statistics. + */ + info(1); + } + pcap_close(pd); + if (VFileName != NULL) { + ret = get_next_file(VFile, VFileLine); + if (ret) { + int new_dlt; + + RFileName = VFileLine; + pd = pcap_open_offline(RFileName, ebuf); + if (pd == NULL) + error("%s", ebuf); +#ifdef HAVE_CAPSICUM + cap_rights_init(&rights, CAP_READ); + if (cap_rights_limit(fileno(pcap_file(pd)), + &rights) < 0 && errno != ENOSYS) { + error("unable to limit pcap descriptor"); + } +#endif + new_dlt = pcap_datalink(pd); + if (new_dlt != dlt) { + /* + * The new file has a different + * link-layer header type from the + * previous one. + */ + if (WFileName != NULL) { + /* + * We're writing raw packets + * that match the filter to + * a pcap file. pcap files + * don't support multiple + * different link-layer + * header types, so we fail + * here. + */ + error("%s: new dlt does not match original", RFileName); + } + + /* + * We're printing the decoded packets; + * switch to the new DLT. + * + * To do that, we need to change + * the printer, change the DLT name, + * and recompile the filter with + * the new DLT. + */ + dlt = new_dlt; + ndo->ndo_if_printer = get_if_printer(ndo, dlt); + if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0) + error("%s", pcap_geterr(pd)); + } + + /* + * Set the filter on the new file. + */ + if (pcap_setfilter(pd, &fcode) < 0) + error("%s", pcap_geterr(pd)); + + /* + * Report the new file. + */ + dlt_name = pcap_datalink_val_to_name(dlt); + if (dlt_name == NULL) { + fprintf(stderr, "reading from file %s, link-type %u\n", + RFileName, dlt); + } else { + fprintf(stderr, + "reading from file %s, link-type %s (%s)\n", + RFileName, dlt_name, + pcap_datalink_val_to_description(dlt)); + } + } + } + } + while (ret != NULL); + + free(cmdbuf); + pcap_freecode(&fcode); + exit_tcpdump(status == -1 ? 1 : 0); +} + +/* make a clean exit on interrupts */ +static RETSIGTYPE +cleanup(int signo _U_) +{ +#ifdef USE_WIN32_MM_TIMER + if (timer_id) + timeKillEvent(timer_id); + timer_id = 0; +#elif defined(HAVE_ALARM) + alarm(0); +#endif + +#ifdef HAVE_PCAP_BREAKLOOP + /* + * We have "pcap_breakloop()"; use it, so that we do as little + * as possible in the signal handler (it's probably not safe + * to do anything with standard I/O streams in a signal handler - + * the ANSI C standard doesn't say it is). + */ + pcap_breakloop(pd); +#else + /* + * We don't have "pcap_breakloop()"; this isn't safe, but + * it's the best we can do. Print the summary if we're + * not reading from a savefile - i.e., if we're doing a + * live capture - and exit. + */ + if (pd != NULL && pcap_file(pd) == NULL) { + /* + * We got interrupted, so perhaps we didn't + * manage to finish a line we were printing. + * Print an extra newline, just in case. + */ + putchar('\n'); + (void)fflush(stdout); + info(1); + } + exit_tcpdump(0); +#endif +} + +/* + On windows, we do not use a fork, so we do not care less about + waiting a child processes to die + */ +#if defined(HAVE_FORK) || defined(HAVE_VFORK) +static RETSIGTYPE +child_cleanup(int signo _U_) +{ + wait(NULL); +} +#endif /* HAVE_FORK && HAVE_VFORK */ + +static void +info(register int verbose) +{ + struct pcap_stat stats; + + /* + * Older versions of libpcap didn't set ps_ifdrop on some + * platforms; initialize it to 0 to handle that. + */ + stats.ps_ifdrop = 0; + if (pcap_stats(pd, &stats) < 0) { + (void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd)); + infoprint = 0; + return; + } + + if (!verbose) + fprintf(stderr, "%s: ", program_name); + + (void)fprintf(stderr, "%u packet%s captured", packets_captured, + PLURAL_SUFFIX(packets_captured)); + if (!verbose) + fputs(", ", stderr); + else + putc('\n', stderr); + (void)fprintf(stderr, "%u packet%s received by filter", stats.ps_recv, + PLURAL_SUFFIX(stats.ps_recv)); + if (!verbose) + fputs(", ", stderr); + else + putc('\n', stderr); + (void)fprintf(stderr, "%u packet%s dropped by kernel", stats.ps_drop, + PLURAL_SUFFIX(stats.ps_drop)); + if (stats.ps_ifdrop != 0) { + if (!verbose) + fputs(", ", stderr); + else + putc('\n', stderr); + (void)fprintf(stderr, "%u packet%s dropped by interface\n", + stats.ps_ifdrop, PLURAL_SUFFIX(stats.ps_ifdrop)); + } else + putc('\n', stderr); + infoprint = 0; +} + +#if defined(HAVE_FORK) || defined(HAVE_VFORK) +#ifdef HAVE_FORK +#define fork_subprocess() fork() +#else +#define fork_subprocess() vfork() +#endif +static void +compress_savefile(const char *filename) +{ + pid_t child; + + child = fork_subprocess(); + if (child == -1) { + fprintf(stderr, + "compress_savefile: fork failed: %s\n", + pcap_strerror(errno)); + return; + } + if (child != 0) { + /* Parent process. */ + return; + } + + /* + * Child process. + * Set to lowest priority so that this doesn't disturb the capture. + */ +#ifdef NZERO + setpriority(PRIO_PROCESS, 0, NZERO - 1); +#else + setpriority(PRIO_PROCESS, 0, 19); +#endif + if (execlp(zflag, zflag, filename, (char *)NULL) == -1) + fprintf(stderr, + "compress_savefile: execlp(%s, %s) failed: %s\n", + zflag, + filename, + pcap_strerror(errno)); +#ifdef HAVE_FORK + exit(1); +#else + _exit(1); +#endif +} +#else /* HAVE_FORK && HAVE_VFORK */ +static void +compress_savefile(const char *filename) +{ + fprintf(stderr, + "compress_savefile failed. Functionality not implemented under your system\n"); +} +#endif /* HAVE_FORK && HAVE_VFORK */ + +static void +dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) +{ + struct dump_info *dump_info; + + ++packets_captured; + + ++infodelay; + + dump_info = (struct dump_info *)user; + + /* + * XXX - this won't force the file to rotate on the specified time + * boundary, but it will rotate on the first packet received after the + * specified Gflag number of seconds. Note: if a Gflag time boundary + * and a Cflag size boundary coincide, the time rotation will occur + * first thereby cancelling the Cflag boundary (since the file should + * be 0). + */ + if (Gflag != 0) { + /* Check if it is time to rotate */ + time_t t; + + /* Get the current time */ + if ((t = time(NULL)) == (time_t)-1) { + error("dump_and_trunc_packet: can't get current_time: %s", + pcap_strerror(errno)); + } + + + /* If the time is greater than the specified window, rotate */ + if (t - Gflag_time >= Gflag) { +#ifdef HAVE_CAPSICUM + FILE *fp; + int fd; +#endif + + /* Update the Gflag_time */ + Gflag_time = t; + /* Update Gflag_count */ + Gflag_count++; + /* + * Close the current file and open a new one. + */ + pcap_dump_close(dump_info->p); + + /* + * Compress the file we just closed, if the user asked for it + */ + if (zflag != NULL) + compress_savefile(dump_info->CurrentFileName); + + /* + * Check to see if we've exceeded the Wflag (when + * not using Cflag). + */ + if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) { + (void)fprintf(stderr, "Maximum file limit reached: %d\n", + Wflag); + info(1); + exit_tcpdump(0); + /* NOTREACHED */ + } + if (dump_info->CurrentFileName != NULL) + free(dump_info->CurrentFileName); + /* Allocate space for max filename + \0. */ + dump_info->CurrentFileName = (char *)malloc(PATH_MAX + 1); + if (dump_info->CurrentFileName == NULL) + error("dump_packet_and_trunc: malloc"); + /* + * Gflag was set otherwise we wouldn't be here. Reset the count + * so multiple files would end with 1,2,3 in the filename. + * The counting is handled with the -C flow after this. + */ + Cflag_count = 0; + + /* + * This is always the first file in the Cflag + * rotation: e.g. 0 + * We also don't need numbering if Cflag is not set. + */ + if (Cflag != 0) + MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0, + WflagChars); + else + MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0, 0); + +#ifdef HAVE_LIBCAP_NG + capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE); + capng_apply(CAPNG_SELECT_BOTH); +#endif /* HAVE_LIBCAP_NG */ +#ifdef HAVE_CAPSICUM + fd = openat(dump_info->dirfd, + dump_info->CurrentFileName, + O_CREAT | O_WRONLY | O_TRUNC, 0644); + if (fd < 0) { + error("unable to open file %s", + dump_info->CurrentFileName); + } + fp = fdopen(fd, "w"); + if (fp == NULL) { + error("unable to fdopen file %s", + dump_info->CurrentFileName); + } + dump_info->p = pcap_dump_fopen(dump_info->pd, fp); +#else /* !HAVE_CAPSICUM */ + dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName); +#endif +#ifdef HAVE_LIBCAP_NG + capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE); + capng_apply(CAPNG_SELECT_BOTH); +#endif /* HAVE_LIBCAP_NG */ + if (dump_info->p == NULL) + error("%s", pcap_geterr(pd)); +#ifdef HAVE_CAPSICUM + set_dumper_capsicum_rights(dump_info->p); +#endif + } + } + + /* + * XXX - this won't prevent capture files from getting + * larger than Cflag - the last packet written to the + * file could put it over Cflag. + */ + if (Cflag != 0) { + long size = pcap_dump_ftell(dump_info->p); + + if (size == -1) + error("ftell fails on output file"); + if (size > Cflag) { +#ifdef HAVE_CAPSICUM + FILE *fp; + int fd; +#endif + + /* + * Close the current file and open a new one. + */ + pcap_dump_close(dump_info->p); + + /* + * Compress the file we just closed, if the user + * asked for it. + */ + if (zflag != NULL) + compress_savefile(dump_info->CurrentFileName); + + Cflag_count++; + if (Wflag > 0) { + if (Cflag_count >= Wflag) + Cflag_count = 0; + } + if (dump_info->CurrentFileName != NULL) + free(dump_info->CurrentFileName); + dump_info->CurrentFileName = (char *)malloc(PATH_MAX + 1); + if (dump_info->CurrentFileName == NULL) + error("dump_packet_and_trunc: malloc"); + MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, Cflag_count, WflagChars); +#ifdef HAVE_LIBCAP_NG + capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE); + capng_apply(CAPNG_SELECT_BOTH); +#endif /* HAVE_LIBCAP_NG */ +#ifdef HAVE_CAPSICUM + fd = openat(dump_info->dirfd, dump_info->CurrentFileName, + O_CREAT | O_WRONLY | O_TRUNC, 0644); + if (fd < 0) { + error("unable to open file %s", + dump_info->CurrentFileName); + } + fp = fdopen(fd, "w"); + if (fp == NULL) { + error("unable to fdopen file %s", + dump_info->CurrentFileName); + } + dump_info->p = pcap_dump_fopen(dump_info->pd, fp); +#else /* !HAVE_CAPSICUM */ + dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName); +#endif +#ifdef HAVE_LIBCAP_NG + capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE); + capng_apply(CAPNG_SELECT_BOTH); +#endif /* HAVE_LIBCAP_NG */ + if (dump_info->p == NULL) + error("%s", pcap_geterr(pd)); +#ifdef HAVE_CAPSICUM + set_dumper_capsicum_rights(dump_info->p); +#endif + } + } + + pcap_dump((u_char *)dump_info->p, h, sp); +#ifdef HAVE_PCAP_DUMP_FLUSH + if (Uflag) + pcap_dump_flush(dump_info->p); +#endif + + --infodelay; + if (infoprint) + info(0); +} + +static void +dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) +{ + ++packets_captured; + + ++infodelay; + + pcap_dump(user, h, sp); +#ifdef HAVE_PCAP_DUMP_FLUSH + if (Uflag) + pcap_dump_flush((pcap_dumper_t *)user); +#endif + + --infodelay; + if (infoprint) + info(0); +} + +static void +print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) +{ + ++packets_captured; + + ++infodelay; + + pretty_print_packet((netdissect_options *)user, h, sp, packets_captured); + + --infodelay; + if (infoprint) + info(0); +} + +#ifdef _WIN32 + /* + * XXX - there should really be libpcap calls to get the version + * number as a string (the string would be generated from #defines + * at run time, so that it's not generated from string constants + * in the library, as, on many UNIX systems, those constants would + * be statically linked into the application executable image, and + * would thus reflect the version of libpcap on the system on + * which the application was *linked*, not the system on which it's + * *running*. + * + * That routine should be documented, unlike the "version[]" + * string, so that UNIX vendors providing their own libpcaps + * don't omit it (as a couple of vendors have...). + * + * Packet.dll should perhaps also export a routine to return the + * version number of the Packet.dll code, to supply the + * "Wpcap_version" information on Windows. + */ + char WDversion[]="current-git.tcpdump.org"; +#if !defined(HAVE_GENERATED_VERSION) + char version[]="current-git.tcpdump.org"; +#endif + char pcap_version[]="current-git.tcpdump.org"; + char Wpcap_version[]="3.1"; +#endif + +#ifdef SIGNAL_REQ_INFO +RETSIGTYPE requestinfo(int signo _U_) +{ + if (infodelay) + ++infoprint; + else + info(0); +} +#endif + +/* + * Called once each second in verbose mode while dumping to file + */ +#ifdef USE_WIN32_MM_TIMER +void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_, + DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_) +{ + if (infodelay == 0) + fprintf(stderr, "Got %u\r", packets_captured); +} +#elif defined(HAVE_ALARM) +static void verbose_stats_dump(int sig _U_) +{ + if (infodelay == 0) + fprintf(stderr, "Got %u\r", packets_captured); + alarm(1); +} +#endif + +USES_APPLE_DEPRECATED_API +static void +print_version(void) +{ + extern char version[]; +#ifndef HAVE_PCAP_LIB_VERSION +#if defined(_WIN32) || defined(HAVE_PCAP_VERSION) + extern char pcap_version[]; +#else /* defined(_WIN32) || defined(HAVE_PCAP_VERSION) */ + static char pcap_version[] = "unknown"; +#endif /* defined(_WIN32) || defined(HAVE_PCAP_VERSION) */ +#endif /* HAVE_PCAP_LIB_VERSION */ + const char *smi_version_string; + +#ifdef HAVE_PCAP_LIB_VERSION +#ifdef _WIN32 + (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version); +#else /* _WIN32 */ + (void)fprintf(stderr, "%s version %s\n", program_name, version); +#endif /* _WIN32 */ + (void)fprintf(stderr, "%s\n",pcap_lib_version()); +#else /* HAVE_PCAP_LIB_VERSION */ +#ifdef _WIN32 + (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version); + (void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version); +#else /* _WIN32 */ + (void)fprintf(stderr, "%s version %s\n", program_name, version); + (void)fprintf(stderr, "libpcap version %s\n", pcap_version); +#endif /* _WIN32 */ +#endif /* HAVE_PCAP_LIB_VERSION */ + +#if defined(HAVE_LIBCRYPTO) && defined(SSLEAY_VERSION) + (void)fprintf (stderr, "%s\n", SSLeay_version(SSLEAY_VERSION)); +#endif + + smi_version_string = nd_smi_version_string(); + if (smi_version_string != NULL) + (void)fprintf (stderr, "SMI-library: %s\n", smi_version_string); + +#if defined(__SANITIZE_ADDRESS__) + (void)fprintf (stderr, "Compiled with AddressSanitizer/GCC.\n"); +#elif defined(__has_feature) +# if __has_feature(address_sanitizer) + (void)fprintf (stderr, "Compiled with AddressSanitizer/CLang.\n"); +# endif +#endif /* __SANITIZE_ADDRESS__ or __has_feature */ +} +USES_APPLE_RST + +static void +print_usage(void) +{ + print_version(); + (void)fprintf(stderr, +"Usage: %s [-aAbd" D_FLAG "efhH" I_FLAG J_FLAG "KlLnNOpqStu" U_FLAG "vxX#]" B_FLAG_USAGE " [ -c count ]\n", program_name); + (void)fprintf(stderr, +"\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n"); + (void)fprintf(stderr, +"\t\t[ -i interface ]" j_FLAG_USAGE " [ -M secret ] [ --number ]\n"); +#ifdef HAVE_PCAP_SETDIRECTION + (void)fprintf(stderr, +"\t\t[ -Q in|out|inout ]\n"); +#endif + (void)fprintf(stderr, +"\t\t[ -r file ] [ -s snaplen ] "); +#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION + (void)fprintf(stderr, "[ --time-stamp-precision precision ]\n"); + (void)fprintf(stderr, +"\t\t"); +#endif +#ifdef HAVE_PCAP_SET_IMMEDIATE_MODE + (void)fprintf(stderr, "[ --immediate-mode ] "); +#endif + (void)fprintf(stderr, "[ -T type ] [ --version ] [ -V file ]\n"); + (void)fprintf(stderr, +"\t\t[ -w file ] [ -W filecount ] [ -y datalinktype ] [ -z postrotate-command ]\n"); + (void)fprintf(stderr, +"\t\t[ -Z user ] [ expression ]\n"); +} +/* + * Local Variables: + * c-style: whitesmith + * c-basic-offset: 8 + * End: + */ |