+ DIR *usbdir;
+ struct dirent *usbitem;
+ size_t name_max;
+ char *name;
+
+ /*
+ * We might have USB sniffing support, so try looking for USB
+ * interfaces.
+ *
+ * We want to report a usbusN device for each USB bus, but
+ * usbusN interfaces might, or might not, exist for them -
+ * we create one if there isn't already one.
+ *
+ * So, instead, we look in /dev/usb for all buses and create
+ * a "usbusN" device for each one.
+ */
+ usbdir = opendir("/dev/usb");
+ if (usbdir == NULL) {
+ /*
+ * Just punt.
+ */
+ return (0);
+ }
+
+ /*
+ * Leave enough room for a 32-bit (10-digit) bus number.
+ * Yes, that's overkill, but we won't be using
+ * the buffer very long.
+ */
+ name_max = USBUS_PREFIX_LEN + 10 + 1;
+ name = malloc(name_max);
+ if (name == NULL) {
+ closedir(usbdir);
+ return (0);
+ }
+ while ((usbitem = readdir(usbdir)) != NULL) {
+ char *p;
+ size_t busnumlen;
+
+ if (strcmp(usbitem->d_name, ".") == 0 ||
+ strcmp(usbitem->d_name, "..") == 0) {
+ /*
+ * Ignore these.
+ */
+ continue;
+ }
+ p = strchr(usbitem->d_name, '.');
+ if (p == NULL)
+ continue;
+ busnumlen = p - usbitem->d_name;
+ memcpy(name, usbus_prefix, USBUS_PREFIX_LEN);
+ memcpy(name + USBUS_PREFIX_LEN, usbitem->d_name, busnumlen);
+ *(name + USBUS_PREFIX_LEN + busnumlen) = '\0';
+ /*
+ * There's an entry in this directory for every USB device,
+ * not for every bus; if there's more than one device on
+ * the bus, there'll be more than one entry for that bus,
+ * so we need to avoid adding multiple capture devices
+ * for each bus.
+ */
+ if (find_or_add_dev(devlistp, name, PCAP_IF_UP,
+ get_usb_if_flags, NULL, errbuf) == NULL) {
+ free(name);
+ closedir(usbdir);
+ return (PCAP_ERROR);
+ }
+ }
+ free(name);
+ closedir(usbdir);
+ return (0);
+}
+#endif
+
+/*
+ * 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);
projects / libpcap / blobdiff