#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().
+ * Some older versions of 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
#include <sys/ioccom.h>
#include <net/bpf.h>
#include <libgen.h>
+#ifdef HAVE_CASPER
+#include <libcasper.h>
+#include <casper/cap_dns.h>
+#include <sys/nv.h>
+#endif /* HAVE_CASPER */
#endif /* HAVE_CAPSICUM */
#include <pcap.h>
#include <signal.h>
#endif /* HAVE_CAP_NG_H */
#endif /* HAVE_LIBCAP_NG */
+#ifdef __FreeBSD__
+#include <sys/sysctl.h>
+#endif /* __FreeBSD__ */
+
#include "netdissect.h"
#include "interface.h"
#include "addrtoname.h"
#endif
static int Bflag; /* buffer size */
-static int Cflag; /* rotate dump files after this many bytes */
+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 */
/*
char *program_name;
+#ifdef HAVE_CASPER
+cap_channel_t *capdns;
+#endif
+
/* Forwards */
-static void error(const char *, ...)
- __attribute__((noreturn))
-#ifdef __ATTRIBUTE___FORMAT_OK
- __attribute__((format (printf, 1, 2)))
-#endif /* __ATTRIBUTE___FORMAT_OK */
- ;
-static void warning(const char *, ...)
-#ifdef __ATTRIBUTE___FORMAT_OK
- __attribute__((format (printf, 1, 2)))
-#endif /* __ATTRIBUTE___FORMAT_OK */
- ;
-static void exit_tcpdump(int) __attribute__((noreturn));
+static NORETURN void error(FORMAT_STRING(const char *), ...) PRINTFLIKE(1, 2);
+static void warning(FORMAT_STRING(const char *), ...) PRINTFLIKE(1, 2);
+static NORETURN void exit_tcpdump(int);
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) __attribute__((noreturn));
-static void show_dlts_and_exit(pcap_t *, const char *device) __attribute__((noreturn));
+static NORETURN void show_tstamp_types_and_exit(pcap_t *, const char *device);
+static NORETURN void show_dlts_and_exit(pcap_t *, const char *device);
#ifdef HAVE_PCAP_FINDALLDEVS
-static void show_devices_and_exit (void) __attribute__((noreturn));
+static NORETURN void show_devices_and_exit(void);
#endif
static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
* 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
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 */
return ret;
}
+#ifdef HAVE_CASPER
+static cap_channel_t *
+capdns_setup(void)
+{
+ cap_channel_t *capcas, *capdnsloc;
+ const char *types[1];
+ int families[2];
+
+ capcas = cap_init();
+ if (capcas == NULL)
+ error("unable to create casper process");
+ capdnsloc = cap_service_open(capcas, "system.dns");
+ /* Casper capability no longer needed. */
+ cap_close(capcas);
+ if (capdnsloc == NULL)
+ error("unable to open system.dns service");
+ /* Limit system.dns to reverse DNS lookups. */
+ types[0] = "ADDR";
+ if (cap_dns_type_limit(capdnsloc, types, 1) < 0)
+ error("unable to limit access to system.dns service");
+ families[0] = AF_INET;
+ families[1] = AF_INET6;
+ if (cap_dns_family_limit(capdnsloc, families, 2) < 0)
+ error("unable to limit access to system.dns service");
+
+ return (capdnsloc);
+}
+#endif /* HAVE_CASPER */
+
#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
static int
tstamp_precision_from_string(const char *precision)
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));
+ if (ndo->ndo_snaplen != 0) {
+ /*
+ * A snapshot length was explicitly specified;
+ * use it.
+ */
+ 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",
/*
* Return an error for our caller to handle.
*/
- pcap_close(pc);
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);
+#ifdef __FreeBSD__
+ else if (status == PCAP_ERROR_RFMON_NOTSUP &&
+ strncmp(device, "wlan", 4) == 0) {
+ char parent[8], newdev[8];
+ char sysctl[32];
+ size_t s = sizeof(parent);
+
+ snprintf(sysctl, sizeof(sysctl),
+ "net.wlan.%d.%%parent", atoi(device + 4));
+ sysctlbyname(sysctl, parent, &s, NULL, 0);
+ strlcpy(newdev, device, sizeof(newdev));
+ /* Suggest a new wlan device. */
+ /* FIXME: incrementing the index this way is not going to work well
+ * when the index is 9 or greater but the only consequence in this
+ * specific case would be an error message that looks a bit odd.
+ */
+ newdev[strlen(newdev)-1]++;
+ error("%s is not a monitor mode VAP\n"
+ "To create a new monitor mode VAP use:\n"
+ " ifconfig %s create wlandev %s wlanmode monitor\n"
+ "and use %s as the tcpdump interface",
+ device, newdev, parent, newdev);
+ }
+#endif
else
error("%s: %s", device,
pcap_statustostr(status));
#endif /* HAVE_PCAP_SETDIRECTION */
#else /* HAVE_PCAP_CREATE */
*ebuf = '\0';
+ /*
+ * If no snapshot length was specified, or a length of 0 was
+ * specified, default to 256KB.
+ */
+ if (ndo->ndo_snaplen == 0)
+ ndo->ndo_snaplen = 262144;
pc = pcap_open_live(device, ndo->ndo_snaplen, !pflag, 1000, ebuf);
if (pc == NULL) {
/*
memset(ndo, 0, sizeof(*ndo));
ndo_set_function_pointers(ndo);
- ndo->ndo_snaplen = DEFAULT_SNAPLEN;
cnt = -1;
device = NULL;
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':
}
/*
- * Let user own process after socket has been opened.
+ * Let user own process after capture device has
+ * been opened.
*/
#ifndef _WIN32
if (setgid(getgid()) != 0 || setuid(getuid()) != 0)
}
i = pcap_snapshot(pd);
if (ndo->ndo_snaplen < i) {
- warning("snaplen raised from %d to %d", ndo->ndo_snaplen, i);
+ if (ndo->ndo_snaplen != 0)
+ warning("snaplen raised from %d to %d", ndo->ndo_snaplen, i);
+ ndo->ndo_snaplen = i;
+ } else if (ndo->ndo_snaplen > i) {
+ warning("snaplen lowered from %d to %d", ndo->ndo_snaplen, i);
ndo->ndo_snaplen = i;
}
if(ndo->ndo_fflag != 0) {
pcap_freecode(&fcode);
exit_tcpdump(0);
}
+
+#ifdef HAVE_CASPER
+ if (!ndo->ndo_nflag)
+ capdns = capdns_setup();
+#endif /* HAVE_CASPER */
+
init_print(ndo, localnet, netmask, timezone_offset);
#ifndef _WIN32
CAP_SETGID,
-1);
}
+ if (chroot_dir) {
+ capng_update(
+ CAPNG_ADD,
+ CAPNG_PERMITTED | CAPNG_EFFECTIVE,
+ CAP_SYS_CHROOT
+ );
+ }
if (WFileName) {
capng_update(
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");
}
#ifdef HAVE_CAPSICUM
- cansandbox = (ndo->ndo_nflag && VFileName == NULL && zflag == NULL);
+ cansandbox = (VFileName == NULL && zflag == NULL);
+#ifdef HAVE_CASPER
+ cansandbox = (cansandbox && (ndo->ndo_nflag || capdns != NULL));
+#else
+ cansandbox = (cansandbox && ndo->ndo_nflag);
+#endif /* HAVE_CASPER */
if (cansandbox && cap_enter() < 0 && errno != ENOSYS)
error("unable to enter the capability mode");
#endif /* HAVE_CAPSICUM */
if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) {
(void)fprintf(stderr, "Maximum file limit reached: %d\n",
Wflag);
+ info(1);
exit_tcpdump(0);
/* NOTREACHED */
}
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
projects / tcpdump / blobdiff