+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_OPEN
+ /*
+ * Is this an rpcap URL?
+ */
+ if (strncmp(device, rpcap_prefix, sizeof(rpcap_prefix) - 1) == 0) {
+ /*
+ * Yes. Open it with pcap_open().
+ */
+ *ebuf = '\0';
+fprintf(stderr, "Opening %s\n", device);
+ pc = pcap_open(device, ndo->ndo_snaplen,
+ pflag ? 0 : PCAP_OPENFLAG_PROMISCUOUS, 1000, NULL,
+ 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);
+ return (pc);
+ }
+#endif /* HAVE_PCAP_OPEN */
+
+#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;
+ 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",
+ 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));
+ }
+#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);
+#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));
+ } 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';
+ /*
+ * 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) {
+ /*
+ * 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);
projects / tcpdump / blobdiff