Use BSS table instead of scan results in need-to-roam determination

The same information is available in the BSS table, so we can reduce the
need for using the raw scan results in wpa_supplicant_need_to_roam().

Signed-hostap: Jouni Malinen <j@w1.fi>

diff --git a/wpa_supplicant/events.c b/wpa_supplicant/events.c
index 7780e9a1070d22bf7e539d5f482eb8db8149723d..d9dfb93465559eacf403b70bfca16e3392dc6433 100644 (file)
--- a/wpa_supplicant/events.c
+++ b/wpa_supplicant/events.c
@@ -966,11 +966,9 @@ static void wpa_supplicant_rsn_preauth_scan_results(
 
 static int wpa_supplicant_need_to_roam(struct wpa_supplicant *wpa_s,
                                       struct wpa_bss *selected,
-                                      struct wpa_ssid *ssid,
-                                      struct wpa_scan_results *scan_res)
+                                      struct wpa_ssid *ssid)
 {
-       size_t i;
-       struct wpa_scan_res *current_bss = NULL;
+       struct wpa_bss *current_bss = NULL;
        int min_diff;
 
        if (wpa_s->reassociate)
@@ -985,25 +983,22 @@ static int wpa_supplicant_need_to_roam(struct wpa_supplicant *wpa_s,
        if (wpas_driver_bss_selection(wpa_s))
                return 0; /* Driver-based roaming */
 
-       for (i = 0; i < scan_res->num; i++) {
-               struct wpa_scan_res *res = scan_res->res[i];
-               const u8 *ie;
-               if (os_memcmp(res->bssid, wpa_s->bssid, ETH_ALEN) != 0)
-                       continue;
-
-               ie = wpa_scan_get_ie(res, WLAN_EID_SSID);
-               if (ie == NULL)
-                       continue;
-               if (ie[1] != wpa_s->current_ssid->ssid_len ||
-                   os_memcmp(ie + 2, wpa_s->current_ssid->ssid, ie[1]) != 0)
-                       continue;
-               current_bss = res;
-               break;
-       }
+       if (wpa_s->current_ssid->ssid)
+               current_bss = wpa_bss_get(wpa_s, wpa_s->bssid,
+                                         wpa_s->current_ssid->ssid,
+                                         wpa_s->current_ssid->ssid_len);
+       if (!current_bss)
+               current_bss = wpa_bss_get_bssid(wpa_s, wpa_s->bssid);
 
        if (!current_bss)
                return 1; /* current BSS not seen in scan results */
 
+       if (current_bss == selected)
+               return 0;
+
+       if (selected->last_update_idx > current_bss->last_update_idx)
+               return 1; /* current BSS not seen in the last scan */
+
 #ifndef CONFIG_NO_ROAMING
        wpa_dbg(wpa_s, MSG_DEBUG, "Considering within-ESS reassociation");
        wpa_dbg(wpa_s, MSG_DEBUG, "Current BSS: " MACSTR " level=%d",
@@ -1165,11 +1160,11 @@ static int _wpa_supplicant_event_scan_results(struct wpa_supplicant *wpa_s,
 
        selected = wpa_supplicant_pick_network(wpa_s, scan_res, &ssid);
 
+       wpa_scan_results_free(scan_res);
+
        if (selected) {
                int skip;
-               skip = !wpa_supplicant_need_to_roam(wpa_s, selected, ssid,
-                                                   scan_res);
-               wpa_scan_results_free(scan_res);
+               skip = !wpa_supplicant_need_to_roam(wpa_s, selected, ssid);
                if (skip) {
                        wpa_supplicant_rsn_preauth_scan_results(wpa_s);
                        return 0;
@@ -1181,7 +1176,6 @@ static int _wpa_supplicant_event_scan_results(struct wpa_supplicant *wpa_s,
                }
                wpa_supplicant_rsn_preauth_scan_results(wpa_s);
        } else {
-               wpa_scan_results_free(scan_res);
                wpa_dbg(wpa_s, MSG_DEBUG, "No suitable network found");
                ssid = wpa_supplicant_pick_new_network(wpa_s);
                if (ssid) {