WPS: Use same UUID in multi-interface case

When generating the UUID based on MAC address, share the same UUID
with all interfaces. This fixes a potential issue with concurrent
dualband APs where the UUID needs to be same for PBC to work properly.

diff --git a/src/ap/wps_hostapd.c b/src/ap/wps_hostapd.c
index 188ad4c..6b7c492 100644 (file)
--- a/src/ap/wps_hostapd.c
+++ b/src/ap/wps_hostapd.c
@@ -499,6 +499,36 @@ static void hostapd_wps_clear_ies(struct hostapd_data *hapd)
 }
 
 
+static int get_uuid_cb(struct hostapd_iface *iface, void *ctx)
+{
+       const u8 **uuid = ctx;
+       size_t j;
+
+       if (iface == NULL)
+               return 0;
+       for (j = 0; j < iface->num_bss; j++) {
+               struct hostapd_data *hapd = iface->bss[j];
+               if (hapd->wps && !is_nil_uuid(hapd->wps->uuid)) {
+                       *uuid = hapd->wps->uuid;
+                       return 1;
+               }
+       }
+
+       return 0;
+}
+
+
+static const u8 * get_own_uuid(struct hostapd_iface *iface)
+{
+       const u8 *uuid;
+       if (iface->for_each_interface == NULL)
+               return NULL;
+       uuid = NULL;
+       iface->for_each_interface(iface->interfaces, get_uuid_cb, &uuid);
+       return uuid;
+}
+
+
 int hostapd_init_wps(struct hostapd_data *hapd,
                     struct hostapd_bss_config *conf)
 {
@@ -522,11 +552,22 @@ int hostapd_init_wps(struct hostapd_data *hapd,
        wps->wps_state = hapd->conf->wps_state;
        wps->ap_setup_locked = hapd->conf->ap_setup_locked;
        if (is_nil_uuid(hapd->conf->uuid)) {
-               uuid_gen_mac_addr(hapd->own_addr, wps->uuid);
-               wpa_hexdump(MSG_DEBUG, "WPS: UUID based on MAC address",
-                           wps->uuid, UUID_LEN);
-       } else
+               const u8 *uuid;
+               uuid = get_own_uuid(hapd->iface);
+               if (uuid) {
+                       os_memcpy(wps->uuid, uuid, UUID_LEN);
+                       wpa_hexdump(MSG_DEBUG, "WPS: Clone UUID from another "
+                                   "interface", wps->uuid, UUID_LEN);
+               } else {
+                       uuid_gen_mac_addr(hapd->own_addr, wps->uuid);
+                       wpa_hexdump(MSG_DEBUG, "WPS: UUID based on MAC "
+                                   "address", wps->uuid, UUID_LEN);
+               }
+       } else {
                os_memcpy(wps->uuid, hapd->conf->uuid, UUID_LEN);
+               wpa_hexdump(MSG_DEBUG, "WPS: Use configured UUID",
+                           wps->uuid, UUID_LEN);
+       }
        wps->ssid_len = hapd->conf->ssid.ssid_len;
        os_memcpy(wps->ssid, hapd->conf->ssid.ssid, wps->ssid_len);
        wps->ap = 1;