+/*
+ * Get additional flags for a device, using SIOCGIFMEDIA.
+ */
+#ifdef SIOCGIFMEDIA
+static int
+get_if_flags(const char *name, bpf_u_int32 *flags, char *errbuf)
+{
+ int sock;
+ struct ifmediareq req;
+
+ sock = socket(AF_INET, SOCK_DGRAM, 0);
+ if (sock == -1) {
+ pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE, errno,
+ "Can't create socket to get media information for %s",
+ name);
+ return (-1);
+ }
+ memset(&req, 0, sizeof(req));
+ pcap_strlcpy(req.ifm_name, name, sizeof(req.ifm_name));
+ if (ioctl(sock, SIOCGIFMEDIA, &req) < 0) {
+ if (errno == EOPNOTSUPP || errno == EINVAL || errno == ENOTTY ||
+ errno == ENODEV || errno == EPERM
+#ifdef EPWROFF
+ || errno == EPWROFF
+#endif
+ ) {
+ /*
+ * Not supported, so we can't provide any
+ * additional information. Assume that
+ * this means that "connected" vs.
+ * "disconnected" doesn't apply.
+ *
+ * The ioctl routine for Apple's pktap devices,
+ * annoyingly, checks for "are you root?" before
+ * checking whether the ioctl is valid, so it
+ * returns EPERM, rather than ENOTSUP, for the
+ * invalid SIOCGIFMEDIA, unless you're root.
+ * So, just as we do for some ethtool ioctls
+ * on Linux, which makes the same mistake, we
+ * also treat EPERM as meaning "not supported".
+ *
+ * And it appears that Apple's llw0 device, which
+ * appears to be part of the Skywalk subsystem:
+ *
+ * http://newosxbook.com/bonus/vol1ch16.html
+ *
+ * can sometimes return EPWROFF ("Device power
+ * is off") for that ioctl, so we treat *that*
+ * as another indication that we can't get a
+ * connection status. (If it *isn't* "powered
+ * off", it's reported as a wireless device,
+ * complete with an active/inactive state.)
+ */
+ *flags |= PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE;
+ close(sock);
+ return (0);
+ }
+ pcap_fmt_errmsg_for_errno(errbuf, PCAP_ERRBUF_SIZE, errno,
+ "SIOCGIFMEDIA on %s failed", name);
+ close(sock);
+ return (-1);
+ }
+ close(sock);
+
+ /*
+ * OK, what type of network is this?
+ */
+ switch (IFM_TYPE(req.ifm_active)) {
+
+ case IFM_IEEE80211:
+ /*
+ * Wireless.
+ */
+ *flags |= PCAP_IF_WIRELESS;
+ break;
+ }
+
+ /*
+ * Do we know whether it's connected?
+ */
+ if (req.ifm_status & IFM_AVALID) {
+ /*
+ * Yes.
+ */
+ if (req.ifm_status & IFM_ACTIVE) {
+ /*
+ * It's connected.
+ */
+ *flags |= PCAP_IF_CONNECTION_STATUS_CONNECTED;
+ } else {
+ /*
+ * It's disconnected.
+ */
+ *flags |= PCAP_IF_CONNECTION_STATUS_DISCONNECTED;
+ }
+ }
+ return (0);
+}
+#else
+static int
+get_if_flags(const char *name _U_, bpf_u_int32 *flags, char *errbuf _U_)
+{
+ /*
+ * Nothing we can do other than mark loopback devices as "the
+ * connected/disconnected status doesn't apply".
+ *
+ * XXX - on Solaris, can we do what the dladm command does,
+ * i.e. get a connected/disconnected indication from a kstat?
+ * (Note that you can also get the link speed, and possibly
+ * other information, from a kstat as well.)
+ */
+ if (*flags & PCAP_IF_LOOPBACK) {
+ /*
+ * Loopback devices aren't wireless, and "connected"/
+ * "disconnected" doesn't apply to them.
+ */
+ *flags |= PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE;
+ return (0);
+ }
+ return (0);
+}
+#endif
+
projects / libpcap / blobdiff