]> The Tcpdump Group git mirrors - tcpdump/blobdiff - tcpdump.c
Handle very large -f files by rejecting them.
[tcpdump] / tcpdump.c
index 282d44c96ffa88a3d3467101aa9cc63147cc7eae..8f27ba2a47fbbf80700df196f679449c10e84f28 100644 (file)
--- a/tcpdump.c
+++ b/tcpdump.c
@@ -56,8 +56,10 @@ The Regents of the University of California.  All rights reserved.\n";
 
 #include <netdissect-stdinc.h>
 
-#ifdef USE_LIBSMI
-#include <smi.h>
+#include <sys/stat.h>
+
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
 #endif
 
 #ifdef HAVE_LIBCRYPTO
@@ -77,12 +79,12 @@ The Regents of the University of California.  All rights reserved.\n";
 #include <sys/capability.h>
 #include <sys/ioccom.h>
 #include <net/bpf.h>
-#include <fcntl.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>
@@ -106,6 +108,7 @@ The Regents of the University of California.  All rights reserved.\n";
 #endif /* HAVE_CAP_NG_H */
 #endif /* HAVE_LIBCAP_NG */
 
+#include "netdissect-stdinc.h"
 #include "netdissect.h"
 #include "interface.h"
 #include "addrtoname.h"
@@ -127,7 +130,8 @@ The Regents of the University of California.  All rights reserved.\n";
 #define SIGNAL_REQ_INFO SIGUSR1
 #endif
 
-static int Cflag;                      /* rotate dump files after this many bytes */
+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 */
 /*
@@ -151,13 +155,16 @@ 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
-int Qflag = -1;                                /* restrict captured packet by send/receive direction */
+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;
@@ -165,12 +172,18 @@ 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(const char *device) __attribute__((noreturn));
-static void show_dlts_and_exit(const char *device) __attribute__((noreturn));
+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 *);
@@ -192,6 +205,7 @@ RETSIGTYPE requestinfo(int);
 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"       },
@@ -202,6 +216,7 @@ static const struct tok status_flags[] = {
        { PCAP_IF_LOOPBACK, "Loopback" },
        { 0, NULL }
 };
+#endif
 
 static pcap_t *pd;
 
@@ -272,23 +287,66 @@ extern
 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(const char *device)
+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(pd, &tstamp_types);
+       n_tstamp_types = pcap_list_tstamp_types(pc, &tstamp_types);
        if (n_tstamp_types < 0)
-               error("%s", pcap_geterr(pd));
+               error("%s", pcap_geterr(pc));
 
        if (n_tstamp_types == 0) {
                fprintf(stderr, "Time stamp type cannot be set for %s\n",
                    device);
-               exit(0);
+               exit_tcpdump(0);
        }
        fprintf(stderr, "Time stamp types for %s (use option -j to set):\n",
            device);
@@ -302,20 +360,20 @@ show_tstamp_types_and_exit(const char *device)
                }
        }
        pcap_free_tstamp_types(tstamp_types);
-       exit(0);
+       exit_tcpdump(0);
 }
 #endif
 
 static void
-show_dlts_and_exit(const char *device)
+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(pd, &dlts);
+       n_dlts = pcap_list_datalinks(pc, &dlts);
        if (n_dlts < 0)
-               error("%s", pcap_geterr(pd));
+               error("%s", pcap_geterr(pc));
        else if (n_dlts == 0 || !dlts)
                error("No data link types.");
 
@@ -355,7 +413,7 @@ show_dlts_and_exit(const char *device)
 #ifdef HAVE_PCAP_FREE_DATALINKS
        pcap_free_datalinks(dlts);
 #endif
-       exit(0);
+       exit_tcpdump(0);
 }
 
 #ifdef HAVE_PCAP_FINDALLDEVS
@@ -377,7 +435,7 @@ show_devices_and_exit (void)
                printf("\n");
        }
        pcap_freealldevs(devlist);
-       exit(0);
+       exit_tcpdump(0);
 }
 #endif /* HAVE_PCAP_FINDALLDEVS */
 
@@ -392,7 +450,7 @@ show_devices_and_exit (void)
  * 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 tospecify that packet comments in pcap-ng files
+ * 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
@@ -535,7 +593,7 @@ droproot(const char *username, const char *chroot_dir)
        if (chroot_dir && !username) {
                fprintf(stderr, "%s: Chroot without dropping root is insecure\n",
                        program_name);
-               exit(1);
+               exit_tcpdump(1);
        }
 
        pw = getpwnam(username);
@@ -544,17 +602,16 @@ droproot(const char *username, const char *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(1);
+                               exit_tcpdump(1);
                        }
                }
 #ifdef HAVE_LIBCAP_NG
                {
                        int ret = capng_change_id(pw->pw_uid, pw->pw_gid, CAPNG_NO_FLAG);
-                       if (ret < 0) {
-                               fprintf(stderr, "error : ret %d\n", ret);
-                       } else {
+                       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 ||
@@ -564,7 +621,7 @@ droproot(const char *username, const char *chroot_dir)
                                (unsigned long)pw->pw_uid,
                                (unsigned long)pw->pw_gid,
                                pcap_strerror(errno));
-                       exit(1);
+                       exit_tcpdump(1);
                }
                else {
                        fprintf(stderr, "dropped privs to %s\n", username);
@@ -574,15 +631,16 @@ droproot(const char *username, const char *chroot_dir)
        else {
                fprintf(stderr, "%s: Couldn't find user '%.32s'\n",
                        program_name, username);
-               exit(1);
+               exit_tcpdump(1);
        }
 #ifdef HAVE_LIBCAP_NG
-       /* We don't need CAP_SETUID and CAP_SETGID any more. */
+       /* 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 */
@@ -642,13 +700,15 @@ static char *
 get_next_file(FILE *VFile, char *ptr)
 {
        char *ret;
+       size_t len;
 
        ret = fgets(ptr, PATH_MAX, VFile);
        if (!ret)
                return NULL;
 
-       if (ptr[strlen(ptr) - 1] == '\n')
-               ptr[strlen(ptr) - 1] = '\0';
+       len = strlen (ptr);
+       if (len > 0 && ptr[len - 1] == '\n')
+               ptr[len - 1] = '\0';
 
        return ret;
 }
@@ -753,6 +813,299 @@ set_dumper_capsicum_rights(pcap_dumper_t *p)
 }
 #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;
+       our_statb buf;
+
+       fd = open(fname, O_RDONLY|O_BINARY);
+       if (fd < 0)
+               error("can't open %s: %s", fname, pcap_strerror(errno));
+
+       if (our_fstat(fd, &buf) < 0)
+               error("can't stat %s: %s", fname, pcap_strerror(errno));
+
+       /*
+        * Reject files whose size doesn't fit into an int; a filter
+        * *that* large will probably be too big.
+        */
+       if (buf.st_size > INT_MAX)
+               error("%s is too large", fname);
+
+       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, (int) 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)
 {
@@ -776,8 +1129,8 @@ main(int argc, char **argv)
        char *ret = NULL;
        char *end;
 #ifdef HAVE_PCAP_FINDALLDEVS
-       pcap_if_t *dev, *devlist;
-       int devnum;
+       pcap_if_t *devlist;
+       long devnum;
 #endif
        int status;
        FILE *VFile;
@@ -785,16 +1138,18 @@ main(int argc, char **argv)
        cap_rights_t rights;
        int cansandbox;
 #endif /* HAVE_CAPSICUM */
-       int Bflag = 0;                  /* buffer size */
-       int jflag = -1;                 /* packet time stamp source */
        int Oflag = 1;                  /* run filter code optimizer */
-       int pflag = 0;                  /* don't go promiscuous */
        int yflag_dlt = -1;
        const char *yflag_dlt_name = NULL;
 
        netdissect_options Ndo;
        netdissect_options *ndo = &Ndo;
-       int immediate_mode = 0;
+
+       /*
+        * Initialize the netdissect code.
+        */
+       if (nd_init(ebuf, sizeof ebuf) == -1)
+               error("%s", ebuf);
 
        memset(ndo, 0, sizeof(*ndo));
        ndo_set_function_pointers(ndo);
@@ -828,10 +1183,6 @@ main(int argc, char **argv)
        if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
                error("%s", ebuf);
 
-#ifdef USE_LIBSMI
-       smiInit("tcpdump");
-#endif
-
        while (
            (op = getopt_long(argc, argv, SHORTOPTS, longopts, NULL)) != -1)
                switch (op) {
@@ -916,7 +1267,7 @@ main(int argc, char **argv)
 
                case 'h':
                        print_usage();
-                       exit(0);
+                       exit_tcpdump(0);
                        break;
 
                case 'H':
@@ -924,42 +1275,6 @@ main(int argc, char **argv)
                        break;
 
                case 'i':
-                       if (optarg[0] == '0' && optarg[1] == 0)
-                               error("Invalid adapter index");
-
-#ifdef HAVE_PCAP_FINDALLDEVS
-                       /*
-                        * If the argument is a number, treat it as
-                        * an index into the list of adapters, as
-                        * printed by "tcpdump -D".
-                        *
-                        * This should be OK on UNIX systems, as interfaces
-                        * shouldn't have names that begin with digits.
-                        * It can be useful on Windows, where more than
-                        * one interface can have the same name.
-                        */
-                       devnum = strtol(optarg, &end, 10);
-                       if (optarg != end && *end == '\0') {
-                               if (devnum < 0)
-                                       error("Invalid adapter index");
-
-                               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);
-                               break;
-                       }
-#endif /* HAVE_PCAP_FINDALLDEVS */
                        device = optarg;
                        break;
 
@@ -1007,16 +1322,14 @@ main(int argc, char **argv)
                        break;
 
                case 'm':
-#ifdef USE_LIBSMI
-                       if (smiLoadModule(optarg) == 0) {
-                               error("could not load MIB module %s", optarg);
+                       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");
                        }
-                       ndo->ndo_mflag = 1;
-#else
-                       (void)fprintf(stderr, "%s: ignoring option `-m %s' ",
-                                     program_name, optarg);
-                       (void)fprintf(stderr, "(no libsmi support)\n");
-#endif
                        break;
 
                case 'M':
@@ -1115,8 +1428,8 @@ main(int argc, char **argv)
                                ndo->ndo_packettype = PT_PGM_ZMTP1;
                        else if (ascii_strcasecmp(optarg, "lmp") == 0)
                                ndo->ndo_packettype = PT_LMP;
-            else if (strcasecmp(optarg, "resp") == 0)
-                ndo->ndo_packettype = PT_RESP;
+                       else if (ascii_strcasecmp(optarg, "resp") == 0)
+                               ndo->ndo_packettype = PT_RESP;
                        else
                                error("unknown packet type `%s'", optarg);
                        break;
@@ -1190,7 +1503,7 @@ main(int argc, char **argv)
 
                case OPTION_VERSION:
                        print_version();
-                       exit(0);
+                       exit_tcpdump(0);
                        break;
 
 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
@@ -1209,7 +1522,7 @@ main(int argc, char **argv)
 
                default:
                        print_usage();
-                       exit(1);
+                       exit_tcpdump(1);
                        /* NOTREACHED */
                }
 
@@ -1341,148 +1654,73 @@ main(int argc, char **argv)
                 * 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);
                }
-#ifdef _WIN32
-               /*
-                * Print a message to the standard error on Windows.
-                * XXX - why do it here, with a different message?
-                */
-               if(strlen(device) == 1) /* we assume that an ASCII string is always longer than 1 char */
-               {                                               /* a Unicode string has a \0 as second byte (so strlen() is 1) */
-                       fprintf(stderr, "%s: listening on %ws\n", program_name, device);
-               }
-               else
-               {
-                       fprintf(stderr, "%s: listening on %s\n", program_name, device);
-               }
-
-               fflush(stderr);
-#endif /* _WIN32 */
-#ifdef HAVE_PCAP_CREATE
-               pd = pcap_create(device, ebuf);
-               if (pd == NULL)
-                       error("%s", ebuf);
-#ifdef HAVE_PCAP_SET_TSTAMP_TYPE
-               if (Jflag)
-                       show_tstamp_types_and_exit(device);
-#endif
-#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
-               status = pcap_set_tstamp_precision(pd, 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(pd, 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?
+                * Try to open the interface with the specified name.
                 */
-               if (pcap_can_set_rfmon(pd) == 1)
-                       supports_monitor_mode = 1;
-               else
-                       supports_monitor_mode = 0;
-               status = pcap_set_snaplen(pd, ndo->ndo_snaplen);
-               if (status != 0)
-                       error("%s: Can't set snapshot length: %s",
-                           device, pcap_statustostr(status));
-               status = pcap_set_promisc(pd, !pflag);
-               if (status != 0)
-                       error("%s: Can't set promiscuous mode: %s",
-                           device, pcap_statustostr(status));
-               if (Iflag) {
-                       status = pcap_set_rfmon(pd, 1);
-                       if (status != 0)
-                               error("%s: Can't set monitor mode: %s",
-                                   device, pcap_statustostr(status));
-               }
-               status = pcap_set_timeout(pd, 1000);
-               if (status != 0)
-                       error("%s: pcap_set_timeout failed: %s",
-                           device, pcap_statustostr(status));
-               if (Bflag != 0) {
-                       status = pcap_set_buffer_size(pd, 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(pd, jflag);
-                       if (status < 0)
-                               error("%s: Can't set time stamp type: %s",
-                                     device, pcap_statustostr(status));
-               }
-#endif
-               status = pcap_activate(pd);
-               if (status < 0) {
+               pd = open_interface(device, ndo, ebuf);
+               if (pd == NULL) {
                        /*
-                        * pcap_activate() failed.
+                        * 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.
                         */
-                       cp = pcap_geterr(pd);
-                       if (status == PCAP_ERROR)
-                               error("%s", cp);
-                       else if ((status == PCAP_ERROR_NO_SUCH_DEVICE ||
-                                 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) {
+#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);
+                       }
+
                        /*
-                        * pcap_activate() succeeded, but it's warning us
-                        * of a problem it had.
+                        * 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.
                         */
-                       cp = pcap_geterr(pd);
-                       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(pd, Qflag);
-                       if (status != 0)
-                               error("%s: pcap_setdirection() failed: %s",
-                                     device,  pcap_geterr(pd));
-               }
-#endif /* HAVE_PCAP_SETDIRECTION */
-#else
-               *ebuf = '\0';
-               pd = pcap_open_live(device, ndo->ndo_snaplen, !pflag, 1000,
-                   ebuf);
-               if (pd == NULL)
                        error("%s", ebuf);
-               else if (*ebuf)
-                       warning("%s", ebuf);
-#endif /* HAVE_PCAP_CREATE */
+#endif /* HAVE_PCAP_FINDALLDEVS */
+               }
+
                /*
                 * Let user own process after socket has been opened.
                 */
@@ -1497,7 +1735,7 @@ main(int argc, char **argv)
                        }
 #endif /* !defined(HAVE_PCAP_CREATE) && defined(_WIN32) */
                if (Lflag)
-                       show_dlts_and_exit(device);
+                       show_dlts_and_exit(pd, device);
                if (yflag_dlt >= 0) {
 #ifdef HAVE_PCAP_SET_DATALINK
                        if (pcap_set_datalink(pd, yflag_dlt) < 0)
@@ -1544,7 +1782,7 @@ main(int argc, char **argv)
                pcap_close(pd);
                free(cmdbuf);
                pcap_freecode(&fcode);
-               exit(0);
+               exit_tcpdump(0);
        }
        init_print(ndo, localnet, netmask, timezone_offset);
 
@@ -1593,6 +1831,13 @@ main(int argc, char **argv)
                                CAP_SETGID,
                                -1);
                }
+               if (chroot_dir) {
+                       capng_update(
+                               CAPNG_ADD,
+                               CAPNG_PERMITTED | CAPNG_EFFECTIVE,
+                               CAP_SYS_CHROOT
+                               );
+               }
 
                if (WFileName) {
                        capng_update(
@@ -1615,7 +1860,12 @@ main(int argc, char **argv)
        if (RFileName == NULL && VFileName == NULL) {
                static const unsigned long cmds[] = { BIOCGSTATS, BIOCROTZBUF };
 
-               cap_rights_init(&rights, CAP_IOCTL, CAP_READ);
+               /*
+                * 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");
@@ -1729,7 +1979,6 @@ main(int argc, char **argv)
 #endif
        }
 
-#ifndef _WIN32
        if (RFileName == NULL) {
                /*
                 * Live capture (if -V was specified, we set RFileName
@@ -1754,7 +2003,6 @@ main(int argc, char **argv)
                }
                (void)fflush(stderr);
        }
-#endif /* _WIN32 */
 
 #ifdef HAVE_CAPSICUM
        cansandbox = (ndo->ndo_nflag && VFileName == NULL && zflag == NULL);
@@ -1879,7 +2127,7 @@ main(int argc, char **argv)
 
        free(cmdbuf);
        pcap_freecode(&fcode);
-       exit(status == -1 ? 1 : 0);
+       exit_tcpdump(status == -1 ? 1 : 0);
 }
 
 /* make a clean exit on interrupts */
@@ -1919,7 +2167,7 @@ cleanup(int signo _U_)
                (void)fflush(stdout);
                info(1);
        }
-       exit(0);
+       exit_tcpdump(0);
 #endif
 }
 
@@ -2092,7 +2340,8 @@ dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *s
                        if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) {
                                (void)fprintf(stderr, "Maximum file limit reached: %d\n",
                                    Wflag);
-                               exit(0);
+                               info(1);
+                               exit_tcpdump(0);
                                /* NOTREACHED */
                        }
                        if (dump_info->CurrentFileName != NULL)
@@ -2334,6 +2583,7 @@ print_version(void)
        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
@@ -2356,9 +2606,17 @@ print_version(void)
        (void)fprintf (stderr, "%s\n", SSLeay_version(SSLEAY_VERSION));
 #endif
 
-#ifdef USE_LIBSMI
-       (void)fprintf (stderr, "SMI-library: %s\n", smi_version_string);
-#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