Do not store raw scan results

Use scan results to update the BSS table and to select the BSS for
connection, but do not store the results for longer time.

wpa_supplicant/bss.h

@@ -15,6 +15,8 @@
 #ifndef BSS_H
 #define BSS_H
 
+struct wpa_scan_res;
+
 #define WPA_BSS_QUAL_INVALID		BIT(0)
 #define WPA_BSS_NOISE_INVALID		BIT(1)
 #define WPA_BSS_LEVEL_INVALID		BIT(2)

wpa_supplicant/events.c

@@ -392,6 +392,7 @@ static int wpa_supplicant_ssid_bss_match(struct wpa_supplicant *wpa_s,
 
 static struct wpa_bss *
 wpa_supplicant_select_bss_wpa(struct wpa_supplicant *wpa_s,
+			      struct wpa_scan_results *scan_res,
 			      struct wpa_ssid *group,
 			      struct wpa_ssid **selected_ssid)
 {
@@ -402,10 +403,10 @@ wpa_supplicant_select_bss_wpa(struct wpa_supplicant *wpa_s,
 	const u8 *ie;
 
 	wpa_printf(MSG_DEBUG, "Try to find WPA-enabled AP");
-	for (i = 0; i < wpa_s->scan_res->num; i++) {
+	for (i = 0; i < scan_res->num; i++) {
 		const u8 *ssid_;
 		u8 wpa_ie_len, rsn_ie_len, ssid_len;
-		bss = wpa_s->scan_res->res[i];
+		bss = scan_res->res[i];
 
 		ie = wpa_scan_get_ie(bss, WLAN_EID_SSID);
 		ssid_ = ie ? ie + 2 : (u8 *) "";
@@ -487,6 +488,7 @@ wpa_supplicant_select_bss_wpa(struct wpa_supplicant *wpa_s,
 
 static struct wpa_bss *
 wpa_supplicant_select_bss_non_wpa(struct wpa_supplicant *wpa_s,
+				  struct wpa_scan_results *scan_res,
 				  struct wpa_ssid *group,
 				  struct wpa_ssid **selected_ssid)
 {
@@ -497,10 +499,10 @@ wpa_supplicant_select_bss_non_wpa(struct wpa_supplicant *wpa_s,
 	const u8 *ie;
 
 	wpa_printf(MSG_DEBUG, "Try to find non-WPA AP");
-	for (i = 0; i < wpa_s->scan_res->num; i++) {
+	for (i = 0; i < scan_res->num; i++) {
 		const u8 *ssid_;
 		u8 wpa_ie_len, rsn_ie_len, ssid_len;
-		bss = wpa_s->scan_res->res[i];
+		bss = scan_res->res[i];
 
 		ie = wpa_scan_get_ie(bss, WLAN_EID_SSID);
 		ssid_ = ie ? ie + 2 : (u8 *) "";
@@ -612,7 +614,9 @@ wpa_supplicant_select_bss_non_wpa(struct wpa_supplicant *wpa_s,
 
 
 static struct wpa_bss *
-wpa_supplicant_select_bss(struct wpa_supplicant *wpa_s, struct wpa_ssid *group,
+wpa_supplicant_select_bss(struct wpa_supplicant *wpa_s,
+			  struct wpa_scan_results *scan_res,
+			  struct wpa_ssid *group,
 			  struct wpa_ssid **selected_ssid)
 {
 	struct wpa_bss *selected;
@@ -621,18 +625,21 @@ wpa_supplicant_select_bss(struct wpa_supplicant *wpa_s, struct wpa_ssid *group,
 		   group->priority);
 
 	/* First, try to find WPA-enabled AP */
-	selected = wpa_supplicant_select_bss_wpa(wpa_s, group, selected_ssid);
+	selected = wpa_supplicant_select_bss_wpa(wpa_s, scan_res, group,
+						 selected_ssid);
 	if (selected)
 		return selected;
 
 	/* If no WPA-enabled AP found, try to find non-WPA AP, if configuration
 	 * allows this. */
-	return wpa_supplicant_select_bss_non_wpa(wpa_s, group, selected_ssid);
+	return wpa_supplicant_select_bss_non_wpa(wpa_s, scan_res, group,
+						 selected_ssid);
 }
 
 
 static struct wpa_bss *
 wpa_supplicant_pick_network(struct wpa_supplicant *wpa_s,
+			    struct wpa_scan_results *scan_res,
 			    struct wpa_ssid **selected_ssid)
 {
 	struct wpa_bss *selected = NULL;
@@ -641,7 +648,7 @@ wpa_supplicant_pick_network(struct wpa_supplicant *wpa_s,
 	while (selected == NULL) {
 		for (prio = 0; prio < wpa_s->conf->num_prio; prio++) {
 			selected = wpa_supplicant_select_bss(
-				wpa_s, wpa_s->conf->pssid[prio],
+				wpa_s, scan_res, wpa_s->conf->pssid[prio],
 				selected_ssid);
 			if (selected)
 				break;
@@ -736,19 +743,21 @@ wpa_supplicant_pick_new_network(struct wpa_supplicant *wpa_s)
 }
 
 
+/* TODO: move the rsn_preauth_scan_result*() to be called from notify.c based
+ * on BSS added and BSS changed events */
 static void wpa_supplicant_rsn_preauth_scan_results(
-	struct wpa_supplicant *wpa_s)
+	struct wpa_supplicant *wpa_s, struct wpa_scan_results *scan_res)
 {
 	int i;
 
 	if (rsn_preauth_scan_results(wpa_s->wpa) < 0)
 		return;
 
-	for (i = wpa_s->scan_res->num - 1; i >= 0; i--) {
+	for (i = scan_res->num - 1; i >= 0; i--) {
 		const u8 *ssid, *rsn;
 		struct wpa_scan_res *r;
 
-		r = wpa_s->scan_res->res[i];
+		r = scan_res->res[i];
 
 		ssid = wpa_scan_get_ie(r, WLAN_EID_SSID);
 		if (ssid == NULL)
@@ -769,11 +778,14 @@ static void wpa_supplicant_event_scan_results(struct wpa_supplicant *wpa_s,
 {
 	struct wpa_bss *selected;
 	struct wpa_ssid *ssid = NULL;
+	struct wpa_scan_results *scan_res;
 
 	wpa_supplicant_notify_scanning(wpa_s, 0);
 
-	if (wpa_supplicant_get_scan_results(wpa_s, data ? &data->scan_info :
-					    NULL, 1) < 0) {
+	scan_res = wpa_supplicant_get_scan_results(wpa_s,
+						   data ? &data->scan_info :
+						   NULL, 1);
+	if (scan_res == NULL) {
 		if (wpa_s->conf->ap_scan == 2)
 			return;
 		wpa_printf(MSG_DEBUG, "Failed to get scan results - try "
@@ -787,7 +799,7 @@ static void wpa_supplicant_event_scan_results(struct wpa_supplicant *wpa_s,
 	 * and there were no results.
 	 */
 	if (wpa_s->scan_res_tried == 1 && wpa_s->conf->ap_scan == 1 &&
-	    wpa_s->scan_res->num == 0) {
+	    scan_res->num == 0) {
 		wpa_msg(wpa_s, MSG_DEBUG, "Cached scan results are "
 			"empty - not posting");
 	} else {
@@ -798,20 +810,27 @@ static void wpa_supplicant_event_scan_results(struct wpa_supplicant *wpa_s,
 
 	wpas_notify_scan_done(wpa_s, 1);
 
-	if ((wpa_s->conf->ap_scan == 2 && !wpas_wps_searching(wpa_s)))
+	if ((wpa_s->conf->ap_scan == 2 && !wpas_wps_searching(wpa_s))) {
+		wpa_scan_results_free(scan_res);
 		return;
+	}
 
 	if (wpa_s->disconnected) {
 		wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
+		wpa_scan_results_free(scan_res);
 		return;
 	}
 
-	if (bgscan_notify_scan(wpa_s) == 1)
+	if (bgscan_notify_scan(wpa_s) == 1) {
+		wpa_scan_results_free(scan_res);
 		return;
+	}
+
+	wpa_supplicant_rsn_preauth_scan_results(wpa_s, scan_res);
 
-	wpa_supplicant_rsn_preauth_scan_results(wpa_s);
+	selected = wpa_supplicant_pick_network(wpa_s, scan_res, &ssid);
+	wpa_scan_results_free(scan_res);
 
-	selected = wpa_supplicant_pick_network(wpa_s, &ssid);
 	if (selected) {
 		wpa_supplicant_connect(wpa_s, selected, ssid);
 	} else {

wpa_supplicant/wpa_supplicant.c

@@ -400,8 +400,6 @@ static void wpa_supplicant_cleanup(struct wpa_supplicant *wpa_s)
 	wpa_s->wpa = NULL;
 	wpa_blacklist_clear(wpa_s);
 
-	wpa_scan_results_free(wpa_s->scan_res);
-	wpa_s->scan_res = NULL;
 	wpa_bss_deinit(wpa_s);
 
 	wpa_supplicant_cancel_scan(wpa_s);
@@ -1569,33 +1567,47 @@ int wpa_supplicant_set_debug_params(struct wpa_global *global, int debug_level,
  * @wpa_s: Pointer to wpa_supplicant data
  * @info: Information about what was scanned or %NULL if not available
  * @new_scan: Whether a new scan was performed
- * Returns: 0 on success, -1 on failure
+ * Returns: Scan results, %NULL on failure
  *
  * This function request the current scan results from the driver and updates
- * the local BSS list wpa_s->bss.
+ * the local BSS list wpa_s->bss. The caller is responsible for freeing the
+ * results with wpa_scan_results_free().
  */
-int wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
-				    struct scan_info *info, int new_scan)
+struct wpa_scan_results *
+wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
+				struct scan_info *info, int new_scan)
 {
+	struct wpa_scan_results *scan_res;
 	size_t i;
 
-	wpa_scan_results_free(wpa_s->scan_res);
 	if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME)
-		wpa_s->scan_res = ieee80211_sta_get_scan_results(wpa_s);
+		scan_res = ieee80211_sta_get_scan_results(wpa_s);
 	else
-		wpa_s->scan_res = wpa_drv_get_scan_results2(wpa_s);
-	if (wpa_s->scan_res == NULL) {
+		scan_res = wpa_drv_get_scan_results2(wpa_s);
+	if (scan_res == NULL) {
 		wpa_printf(MSG_DEBUG, "Failed to get scan results");
-		return -1;
+		return NULL;
 	}
 
-	wpa_scan_sort_results(wpa_s->scan_res);
+	wpa_scan_sort_results(scan_res);
 
 	wpa_bss_update_start(wpa_s);
-	for (i = 0; i < wpa_s->scan_res->num; i++)
-		wpa_bss_update_scan_res(wpa_s, wpa_s->scan_res->res[i]);
+	for (i = 0; i < scan_res->num; i++)
+		wpa_bss_update_scan_res(wpa_s, scan_res->res[i]);
 	wpa_bss_update_end(wpa_s, info, new_scan);
 
+	return scan_res;
+}
+
+
+int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
+{
+	struct wpa_scan_results *scan_res;
+	scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
+	if (scan_res == NULL)
+		return -1;
+	wpa_scan_results_free(scan_res);
+
 	return 0;
 }
 

wpa_supplicant/wpa_supplicant_i.h

@@ -28,8 +28,6 @@ extern const char *wpa_supplicant_full_license4;
 extern const char *wpa_supplicant_full_license5;
 #endif /* CONFIG_NO_STDOUT_DEBUG */
 
-struct wpa_scan_result;
-struct wpa_scan_res;
 struct wpa_sm;
 struct wpa_supplicant;
 struct ibss_rsn;
@@ -345,7 +343,6 @@ struct wpa_supplicant {
 					  */
 #define WILDCARD_SSID_SCAN ((struct wpa_ssid *) 1)
 
-	struct wpa_scan_results *scan_res;
 	struct dl_list bss; /* struct wpa_bss::list */
 	struct dl_list bss_id; /* struct wpa_bss::list_id */
 	size_t num_bss;
@@ -446,8 +443,10 @@ void wpa_supplicant_associate(struct wpa_supplicant *wpa_s,
 void wpa_supplicant_set_non_wpa_policy(struct wpa_supplicant *wpa_s,
 				       struct wpa_ssid *ssid);
 void wpa_supplicant_initiate_eapol(struct wpa_supplicant *wpa_s);
-int wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
-				    struct scan_info *info, int new_scan);
+struct wpa_scan_results *
+wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
+				struct scan_info *info, int new_scan);
+int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s);
 void wpa_clear_keys(struct wpa_supplicant *wpa_s, const u8 *addr);
 void wpa_supplicant_req_auth_timeout(struct wpa_supplicant *wpa_s,
 				     int sec, int usec);

wpa_supplicant/wpas_glue.c

@@ -343,9 +343,8 @@ static int wpa_supplicant_get_beacon_ie(void *ctx)
 
 	/* No WPA/RSN IE found in the cached scan results. Try to get updated
 	 * scan results from the driver. */
-	if (wpa_supplicant_get_scan_results(wpa_s, NULL, 0) < 0) {
+	if (wpa_supplicant_update_scan_results(wpa_s) < 0)
 		return -1;
-	}
 
 	return wpa_get_beacon_ie(wpa_s);
 }

wpa_supplicant/wps_supplicant.h

@@ -21,6 +21,7 @@
 #include "wps/wps_defs.h"
 
 struct wpa_bss;
+struct wpa_scan_res;
 
 struct wps_new_ap_settings {
 	const char *ssid_hex;