Merge branch 'moonshot' of ssh://moonshot.suchdamage.org:822/srv/git/libeap into...
[libeap.git] / wpa_supplicant / scan.c
index 67e2282..ee105d9 100644 (file)
@@ -1,6 +1,6 @@
 /*
  * WPA Supplicant - Scanning
- * Copyright (c) 2003-2008, Jouni Malinen <j@w1.fi>
+ * Copyright (c) 2003-2010, Jouni Malinen <j@w1.fi>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
  * See README and COPYING for more details.
  */
 
-#include "includes.h"
+#include "utils/includes.h"
 
-#include "common.h"
-#include "eloop.h"
+#include "utils/common.h"
+#include "utils/eloop.h"
+#include "common/ieee802_11_defs.h"
 #include "config.h"
 #include "wpa_supplicant_i.h"
+#include "driver_i.h"
 #include "mlme.h"
 #include "wps_supplicant.h"
+#include "p2p_supplicant.h"
+#include "p2p/p2p.h"
+#include "notify.h"
+#include "bss.h"
+#include "scan.h"
 
 
 static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s)
@@ -31,8 +38,11 @@ static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s)
        if (ssid == NULL)
                return;
 
-       if (wpa_s->current_ssid == NULL)
+       if (wpa_s->current_ssid == NULL) {
                wpa_s->current_ssid = ssid;
+               if (wpa_s->current_ssid != NULL)
+                       wpas_notify_network_changed(wpa_s);
+       }
        wpa_supplicant_initiate_eapol(wpa_s);
        wpa_printf(MSG_DEBUG, "Already associated with a configured network - "
                   "generating associated event");
@@ -65,44 +75,207 @@ static int wpas_wps_in_use(struct wpa_config *conf,
 }
 #endif /* CONFIG_WPS */
 
+
+int wpa_supplicant_enabled_networks(struct wpa_config *conf)
+{
+       struct wpa_ssid *ssid = conf->ssid;
+       while (ssid) {
+               if (!ssid->disabled)
+                       return 1;
+               ssid = ssid->next;
+       }
+       return 0;
+}
+
+
+static void wpa_supplicant_assoc_try(struct wpa_supplicant *wpa_s,
+                                    struct wpa_ssid *ssid)
+{
+       while (ssid) {
+               if (!ssid->disabled)
+                       break;
+               ssid = ssid->next;
+       }
+
+       /* ap_scan=2 mode - try to associate with each SSID. */
+       if (ssid == NULL) {
+               wpa_printf(MSG_DEBUG, "wpa_supplicant_scan: Reached "
+                          "end of scan list - go back to beginning");
+               wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
+               wpa_supplicant_req_scan(wpa_s, 0, 0);
+               return;
+       }
+       if (ssid->next) {
+               /* Continue from the next SSID on the next attempt. */
+               wpa_s->prev_scan_ssid = ssid;
+       } else {
+               /* Start from the beginning of the SSID list. */
+               wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
+       }
+       wpa_supplicant_associate(wpa_s, NULL, ssid);
+}
+
+
+static int int_array_len(const int *a)
+{
+       int i;
+       for (i = 0; a && a[i]; i++)
+               ;
+       return i;
+}
+
+
+static void int_array_concat(int **res, const int *a)
+{
+       int reslen, alen, i;
+       int *n;
+
+       reslen = int_array_len(*res);
+       alen = int_array_len(a);
+
+       n = os_realloc(*res, (reslen + alen + 1) * sizeof(int));
+       if (n == NULL) {
+               os_free(*res);
+               *res = NULL;
+               return;
+       }
+       for (i = 0; i <= alen; i++)
+               n[reslen + i] = a[i];
+       *res = n;
+}
+
+
+static int freq_cmp(const void *a, const void *b)
+{
+       int _a = *(int *) a;
+       int _b = *(int *) b;
+
+       if (_a == 0)
+               return 1;
+       if (_b == 0)
+               return -1;
+       return _a - _b;
+}
+
+
+static void int_array_sort_unique(int *a)
+{
+       int alen;
+       int i, j;
+
+       if (a == NULL)
+               return;
+
+       alen = int_array_len(a);
+       qsort(a, alen, sizeof(int), freq_cmp);
+
+       i = 0;
+       j = 1;
+       while (a[i] && a[j]) {
+               if (a[i] == a[j]) {
+                       j++;
+                       continue;
+               }
+               a[++i] = a[j++];
+       }
+       if (a[i])
+               i++;
+       a[i] = 0;
+}
+
+
+int wpa_supplicant_trigger_scan(struct wpa_supplicant *wpa_s,
+                               struct wpa_driver_scan_params *params)
+{
+       int ret;
+
+       wpa_supplicant_notify_scanning(wpa_s, 1);
+
+       if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME)
+               ret = ieee80211_sta_req_scan(wpa_s, params);
+       else
+               ret = wpa_drv_scan(wpa_s, params);
+
+       if (ret) {
+               wpa_supplicant_notify_scanning(wpa_s, 0);
+               wpas_notify_scan_done(wpa_s, 0);
+       } else
+               wpa_s->scan_runs++;
+
+       return ret;
+}
+
+
+static struct wpa_driver_scan_filter *
+wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids)
+{
+       struct wpa_driver_scan_filter *ssids;
+       struct wpa_ssid *ssid;
+       size_t count;
+
+       *num_ssids = 0;
+       if (!conf->filter_ssids)
+               return NULL;
+
+       for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) {
+               if (ssid->ssid && ssid->ssid_len)
+                       count++;
+       }
+       if (count == 0)
+               return NULL;
+       ssids = os_zalloc(count * sizeof(struct wpa_driver_scan_filter));
+       if (ssids == NULL)
+               return NULL;
+
+       for (ssid = conf->ssid; ssid; ssid = ssid->next) {
+               if (!ssid->ssid || !ssid->ssid_len)
+                       continue;
+               os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len);
+               ssids[*num_ssids].ssid_len = ssid->ssid_len;
+               (*num_ssids)++;
+       }
+
+       return ssids;
+}
+
+
 static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
 {
        struct wpa_supplicant *wpa_s = eloop_ctx;
        struct wpa_ssid *ssid;
-       int enabled, scan_req = 0, ret;
+       int scan_req = 0, ret;
        struct wpabuf *wps_ie = NULL;
-       const u8 *extra_ie = NULL;
-       size_t extra_ie_len = 0;
-       int wps = 0;
 #ifdef CONFIG_WPS
+       int wps = 0;
        enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
 #endif /* CONFIG_WPS */
+       struct wpa_driver_scan_params params;
+       size_t max_ssids;
+       enum wpa_states prev_state;
 
-       if (wpa_s->disconnected && !wpa_s->scan_req)
+       if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
+               wpa_printf(MSG_DEBUG, "Skip scan - interface disabled");
                return;
+       }
 
-       enabled = 0;
-       ssid = wpa_s->conf->ssid;
-       while (ssid) {
-               if (!ssid->disabled) {
-                       enabled++;
-                       break;
-               }
-               ssid = ssid->next;
+       if (wpa_s->disconnected && !wpa_s->scan_req) {
+               wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
+               return;
        }
-       if (!enabled && !wpa_s->scan_req) {
+
+       if (!wpa_supplicant_enabled_networks(wpa_s->conf) &&
+           !wpa_s->scan_req) {
                wpa_printf(MSG_DEBUG, "No enabled networks - do not scan");
                wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
                return;
        }
-       scan_req = wpa_s->scan_req;
-       wpa_s->scan_req = 0;
 
        if (wpa_s->conf->ap_scan != 0 &&
-           wpa_s->driver && IS_WIRED(wpa_s->driver)) {
+           (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
                wpa_printf(MSG_DEBUG, "Using wired authentication - "
                           "overriding ap_scan configuration");
                wpa_s->conf->ap_scan = 0;
+               wpas_notify_ap_scan_changed(wpa_s);
        }
 
        if (wpa_s->conf->ap_scan == 0) {
@@ -110,12 +283,32 @@ static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
                return;
        }
 
+       if ((wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME) ||
+           wpa_s->conf->ap_scan == 2)
+               max_ssids = 1;
+       else {
+               max_ssids = wpa_s->max_scan_ssids;
+               if (max_ssids > WPAS_MAX_SCAN_SSIDS)
+                       max_ssids = WPAS_MAX_SCAN_SSIDS;
+       }
+
+#ifdef CONFIG_WPS
+       wps = wpas_wps_in_use(wpa_s->conf, &req_type);
+#endif /* CONFIG_WPS */
+
+       scan_req = wpa_s->scan_req;
+       wpa_s->scan_req = 0;
+
+       os_memset(&params, 0, sizeof(params));
+
+       prev_state = wpa_s->wpa_state;
        if (wpa_s->wpa_state == WPA_DISCONNECTED ||
            wpa_s->wpa_state == WPA_INACTIVE)
                wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
 
+       /* Find the starting point from which to continue scanning */
        ssid = wpa_s->conf->ssid;
-       if (wpa_s->prev_scan_ssid != BROADCAST_SSID_SCAN) {
+       if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
                while (ssid) {
                        if (ssid == wpa_s->prev_scan_ssid) {
                                ssid = ssid->next;
@@ -124,88 +317,151 @@ static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
                        ssid = ssid->next;
                }
        }
-       while (ssid) {
-               if (!ssid->disabled &&
-                   (ssid->scan_ssid || wpa_s->conf->ap_scan == 2))
-                       break;
-               ssid = ssid->next;
-       }
 
-       if (scan_req != 2 && wpa_s->conf->ap_scan == 2) {
+       if (scan_req != 2 && (wpa_s->conf->ap_scan == 2 ||
+                             wpa_s->connect_without_scan)) {
+               wpa_s->connect_without_scan = 0;
+               wpa_supplicant_assoc_try(wpa_s, ssid);
+               return;
+       } else if (wpa_s->conf->ap_scan == 2) {
                /*
-                * ap_scan=2 mode - try to associate with each SSID instead of
-                * scanning for each scan_ssid=1 network.
+                * User-initiated scan request in ap_scan == 2; scan with
+                * wildcard SSID.
                 */
-               if (ssid == NULL) {
-                       wpa_printf(MSG_DEBUG, "wpa_supplicant_scan: Reached "
-                                  "end of scan list - go back to beginning");
-                       wpa_s->prev_scan_ssid = BROADCAST_SSID_SCAN;
-                       wpa_supplicant_req_scan(wpa_s, 0, 0);
-                       return;
+               ssid = NULL;
+       } else {
+               struct wpa_ssid *start = ssid, *tssid;
+               int freqs_set = 0;
+               if (ssid == NULL && max_ssids > 1)
+                       ssid = wpa_s->conf->ssid;
+               while (ssid) {
+                       if (!ssid->disabled && ssid->scan_ssid) {
+                               wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
+                                                 ssid->ssid, ssid->ssid_len);
+                               params.ssids[params.num_ssids].ssid =
+                                       ssid->ssid;
+                               params.ssids[params.num_ssids].ssid_len =
+                                       ssid->ssid_len;
+                               params.num_ssids++;
+                               if (params.num_ssids + 1 >= max_ssids)
+                                       break;
+                       }
+                       ssid = ssid->next;
+                       if (ssid == start)
+                               break;
+                       if (ssid == NULL && max_ssids > 1 &&
+                           start != wpa_s->conf->ssid)
+                               ssid = wpa_s->conf->ssid;
                }
-               if (ssid->next) {
-                       /* Continue from the next SSID on the next attempt. */
-                       wpa_s->prev_scan_ssid = ssid;
-               } else {
-                       /* Start from the beginning of the SSID list. */
-                       wpa_s->prev_scan_ssid = BROADCAST_SSID_SCAN;
+
+               for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) {
+                       if (tssid->disabled)
+                               continue;
+                       if ((params.freqs || !freqs_set) && tssid->scan_freq) {
+                               int_array_concat(&params.freqs,
+                                                tssid->scan_freq);
+                       } else {
+                               os_free(params.freqs);
+                               params.freqs = NULL;
+                       }
+                       freqs_set = 1;
                }
-               wpa_supplicant_associate(wpa_s, NULL, ssid);
-               return;
+               int_array_sort_unique(params.freqs);
        }
 
-       wpa_printf(MSG_DEBUG, "Starting AP scan (%s SSID)",
-                  ssid ? "specific": "broadcast");
        if (ssid) {
-               wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
-                                 ssid->ssid, ssid->ssid_len);
                wpa_s->prev_scan_ssid = ssid;
-       } else
-               wpa_s->prev_scan_ssid = BROADCAST_SSID_SCAN;
+               if (max_ssids > 1) {
+                       wpa_printf(MSG_DEBUG, "Include wildcard SSID in the "
+                                  "scan request");
+                       params.num_ssids++;
+               }
+               wpa_printf(MSG_DEBUG, "Starting AP scan for specific SSID(s)");
+       } else {
+               wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
+               params.num_ssids++;
+               wpa_printf(MSG_DEBUG, "Starting AP scan for wildcard SSID");
+       }
 
-#ifdef CONFIG_WPS
-       wps = wpas_wps_in_use(wpa_s->conf, &req_type);
-#endif /* CONFIG_WPS */
+#ifdef CONFIG_P2P
+       wpa_s->wps->dev.p2p = 1;
+       if (!wps) {
+               wps = 1;
+               req_type = WPS_REQ_ENROLLEE_INFO;
+       }
 
-       if (wpa_s->scan_res_tried == 0 && wpa_s->conf->ap_scan == 1 &&
-           !wpa_s->use_client_mlme && wps != 2) {
-               wpa_s->scan_res_tried++;
-               wpa_s->scan_req = scan_req;
-               wpa_printf(MSG_DEBUG, "Trying to get current scan results "
-                          "first without requesting a new scan to speed up "
-                          "initial association");
-               wpa_supplicant_event(wpa_s, EVENT_SCAN_RESULTS, NULL);
-               return;
+       if (params.freqs == NULL && wpa_s->p2p_in_provisioning &&
+           wpa_s->go_params) {
+               /* Optimize provisioning state scan based on GO information */
+               if (wpa_s->p2p_in_provisioning < 5 &&
+                   wpa_s->go_params->freq > 0) {
+                       wpa_printf(MSG_DEBUG, "P2P: Scan only GO preferred "
+                                  "frequency %d MHz",
+                                  wpa_s->go_params->freq);
+                       params.freqs = os_zalloc(2 * sizeof(int));
+                       if (params.freqs)
+                               params.freqs[0] = wpa_s->go_params->freq;
+               } else if (wpa_s->go_params->freq_list[0]) {
+                       wpa_printf(MSG_DEBUG, "P2P: Scan only common "
+                                  "channels");
+                       int_array_concat(&params.freqs,
+                                        wpa_s->go_params->freq_list);
+                       if (params.freqs)
+                               int_array_sort_unique(params.freqs);
+               }
+               wpa_s->p2p_in_provisioning++;
        }
+#endif /* CONFIG_P2P */
 
 #ifdef CONFIG_WPS
+       if (params.freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) {
+               /*
+                * Optimize post-provisioning scan based on channel used
+                * during provisioning.
+                */
+               wpa_printf(MSG_DEBUG, "WPS: Scan only frequency %u MHz that "
+                          "was used during provisioning", wpa_s->wps_freq);
+               params.freqs = os_zalloc(2 * sizeof(int));
+               if (params.freqs)
+                       params.freqs[0] = wpa_s->wps_freq;
+               wpa_s->after_wps--;
+       }
+
        if (wps) {
                wps_ie = wps_build_probe_req_ie(wps == 2, &wpa_s->wps->dev,
                                                wpa_s->wps->uuid, req_type);
                if (wps_ie) {
-                       extra_ie = wpabuf_head(wps_ie);
-                       extra_ie_len = wpabuf_len(wps_ie);
+                       params.extra_ies = wpabuf_head(wps_ie);
+                       params.extra_ies_len = wpabuf_len(wps_ie);
                }
        }
 #endif /* CONFIG_WPS */
 
-       if (wpa_s->use_client_mlme) {
-               ieee80211_sta_set_probe_req_ie(wpa_s, extra_ie, extra_ie_len);
-               ret = ieee80211_sta_req_scan(wpa_s, ssid ? ssid->ssid : NULL,
-                                            ssid ? ssid->ssid_len : 0);
-       } else {
-               wpa_drv_set_probe_req_ie(wpa_s, extra_ie, extra_ie_len);
-               ret = wpa_drv_scan(wpa_s, ssid ? ssid->ssid : NULL,
-                                  ssid ? ssid->ssid_len : 0);
+#ifdef CONFIG_P2P
+       if (wps_ie) {
+               if (wpabuf_resize(&wps_ie, 100) == 0) {
+                       wpas_p2p_scan_ie(wpa_s, wps_ie);
+                       params.extra_ies = wpabuf_head(wps_ie);
+                       params.extra_ies_len = wpabuf_len(wps_ie);
+               }
        }
+#endif /* CONFIG_P2P */
+
+       params.filter_ssids = wpa_supplicant_build_filter_ssids(
+               wpa_s->conf, &params.num_filter_ssids);
+
+       ret = wpa_supplicant_trigger_scan(wpa_s, &params);
 
        wpabuf_free(wps_ie);
+       os_free(params.freqs);
+       os_free(params.filter_ssids);
 
        if (ret) {
                wpa_printf(MSG_WARNING, "Failed to initiate AP scan.");
-               wpa_supplicant_req_scan(wpa_s, 10, 0);
-       } else
-               wpa_s->scan_runs++;
+               if (prev_state != wpa_s->wpa_state)
+                       wpa_supplicant_set_state(wpa_s, prev_state);
+               wpa_supplicant_req_scan(wpa_s, 1, 0);
+       }
 }
 
 
@@ -261,3 +517,311 @@ void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
        wpa_msg(wpa_s, MSG_DEBUG, "Cancelling scan request");
        eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 }
+
+
+void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
+                                   int scanning)
+{
+       if (wpa_s->scanning != scanning) {
+               wpa_s->scanning = scanning;
+               wpas_notify_scanning(wpa_s);
+       }
+}
+
+
+static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
+{
+       int rate = 0;
+       const u8 *ie;
+       int i;
+
+       ie = wpa_scan_get_ie(res, WLAN_EID_SUPP_RATES);
+       for (i = 0; ie && i < ie[1]; i++) {
+               if ((ie[i + 2] & 0x7f) > rate)
+                       rate = ie[i + 2] & 0x7f;
+       }
+
+       ie = wpa_scan_get_ie(res, WLAN_EID_EXT_SUPP_RATES);
+       for (i = 0; ie && i < ie[1]; i++) {
+               if ((ie[i + 2] & 0x7f) > rate)
+                       rate = ie[i + 2] & 0x7f;
+       }
+
+       return rate;
+}
+
+
+const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
+{
+       const u8 *end, *pos;
+
+       pos = (const u8 *) (res + 1);
+       end = pos + res->ie_len;
+
+       while (pos + 1 < end) {
+               if (pos + 2 + pos[1] > end)
+                       break;
+               if (pos[0] == ie)
+                       return pos;
+               pos += 2 + pos[1];
+       }
+
+       return NULL;
+}
+
+
+const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
+                                 u32 vendor_type)
+{
+       const u8 *end, *pos;
+
+       pos = (const u8 *) (res + 1);
+       end = pos + res->ie_len;
+
+       while (pos + 1 < end) {
+               if (pos + 2 + pos[1] > end)
+                       break;
+               if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
+                   vendor_type == WPA_GET_BE32(&pos[2]))
+                       return pos;
+               pos += 2 + pos[1];
+       }
+
+       return NULL;
+}
+
+
+struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
+                                            u32 vendor_type)
+{
+       struct wpabuf *buf;
+       const u8 *end, *pos;
+
+       buf = wpabuf_alloc(res->ie_len);
+       if (buf == NULL)
+               return NULL;
+
+       pos = (const u8 *) (res + 1);
+       end = pos + res->ie_len;
+
+       while (pos + 1 < end) {
+               if (pos + 2 + pos[1] > end)
+                       break;
+               if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
+                   vendor_type == WPA_GET_BE32(&pos[2]))
+                       wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
+               pos += 2 + pos[1];
+       }
+
+       if (wpabuf_len(buf) == 0) {
+               wpabuf_free(buf);
+               buf = NULL;
+       }
+
+       return buf;
+}
+
+
+struct wpabuf * wpa_scan_get_vendor_ie_multi_beacon(
+       const struct wpa_scan_res *res, u32 vendor_type)
+{
+       struct wpabuf *buf;
+       const u8 *end, *pos;
+
+       if (res->beacon_ie_len == 0)
+               return NULL;
+       buf = wpabuf_alloc(res->beacon_ie_len);
+       if (buf == NULL)
+               return NULL;
+
+       pos = (const u8 *) (res + 1);
+       pos += res->ie_len;
+       end = pos + res->beacon_ie_len;
+
+       while (pos + 1 < end) {
+               if (pos + 2 + pos[1] > end)
+                       break;
+               if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
+                   vendor_type == WPA_GET_BE32(&pos[2]))
+                       wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
+               pos += 2 + pos[1];
+       }
+
+       if (wpabuf_len(buf) == 0) {
+               wpabuf_free(buf);
+               buf = NULL;
+       }
+
+       return buf;
+}
+
+
+/* Compare function for sorting scan results. Return >0 if @b is considered
+ * better. */
+static int wpa_scan_result_compar(const void *a, const void *b)
+{
+       struct wpa_scan_res **_wa = (void *) a;
+       struct wpa_scan_res **_wb = (void *) b;
+       struct wpa_scan_res *wa = *_wa;
+       struct wpa_scan_res *wb = *_wb;
+       int wpa_a, wpa_b, maxrate_a, maxrate_b;
+
+       /* WPA/WPA2 support preferred */
+       wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
+               wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
+       wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
+               wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
+
+       if (wpa_b && !wpa_a)
+               return 1;
+       if (!wpa_b && wpa_a)
+               return -1;
+
+       /* privacy support preferred */
+       if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
+           (wb->caps & IEEE80211_CAP_PRIVACY))
+               return 1;
+       if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
+           (wb->caps & IEEE80211_CAP_PRIVACY) == 0)
+               return -1;
+
+       /* best/max rate preferred if signal level close enough XXX */
+       if ((wa->level && wb->level && abs(wb->level - wa->level) < 5) ||
+           (wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
+               maxrate_a = wpa_scan_get_max_rate(wa);
+               maxrate_b = wpa_scan_get_max_rate(wb);
+               if (maxrate_a != maxrate_b)
+                       return maxrate_b - maxrate_a;
+       }
+
+       /* use freq for channel preference */
+
+       /* all things being equal, use signal level; if signal levels are
+        * identical, use quality values since some drivers may only report
+        * that value and leave the signal level zero */
+       if (wb->level == wa->level)
+               return wb->qual - wa->qual;
+       return wb->level - wa->level;
+}
+
+
+#ifdef CONFIG_WPS
+/* Compare function for sorting scan results when searching a WPS AP for
+ * provisioning. Return >0 if @b is considered better. */
+static int wpa_scan_result_wps_compar(const void *a, const void *b)
+{
+       struct wpa_scan_res **_wa = (void *) a;
+       struct wpa_scan_res **_wb = (void *) b;
+       struct wpa_scan_res *wa = *_wa;
+       struct wpa_scan_res *wb = *_wb;
+       int uses_wps_a, uses_wps_b;
+       struct wpabuf *wps_a, *wps_b;
+       int res;
+
+       /* Optimization - check WPS IE existence before allocated memory and
+        * doing full reassembly. */
+       uses_wps_a = wpa_scan_get_vendor_ie(wa, WPS_IE_VENDOR_TYPE) != NULL;
+       uses_wps_b = wpa_scan_get_vendor_ie(wb, WPS_IE_VENDOR_TYPE) != NULL;
+       if (uses_wps_a && !uses_wps_b)
+               return -1;
+       if (!uses_wps_a && uses_wps_b)
+               return 1;
+
+       if (uses_wps_a && uses_wps_b) {
+               wps_a = wpa_scan_get_vendor_ie_multi(wa, WPS_IE_VENDOR_TYPE);
+               wps_b = wpa_scan_get_vendor_ie_multi(wb, WPS_IE_VENDOR_TYPE);
+               res = wps_ap_priority_compar(wps_a, wps_b);
+               wpabuf_free(wps_a);
+               wpabuf_free(wps_b);
+               if (res)
+                       return res;
+       }
+
+       /*
+        * Do not use current AP security policy as a sorting criteria during
+        * WPS provisioning step since the AP may get reconfigured at the
+        * completion of provisioning.
+        */
+
+       /* all things being equal, use signal level; if signal levels are
+        * identical, use quality values since some drivers may only report
+        * that value and leave the signal level zero */
+       if (wb->level == wa->level)
+               return wb->qual - wa->qual;
+       return wb->level - wa->level;
+}
+#endif /* CONFIG_WPS */
+
+
+/**
+ * wpa_supplicant_get_scan_results - Get scan results
+ * @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: 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 caller is responsible for freeing the
+ * results with wpa_scan_results_free().
+ */
+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;
+       int (*compar)(const void *, const void *) = wpa_scan_result_compar;
+
+       if (wpa_s->drv_flags & WPA_DRIVER_FLAGS_USER_SPACE_MLME)
+               scan_res = ieee80211_sta_get_scan_results(wpa_s);
+       else
+               scan_res = wpa_drv_get_scan_results2(wpa_s);
+       if (scan_res == NULL) {
+               wpa_printf(MSG_DEBUG, "Failed to get scan results");
+               return NULL;
+       }
+
+#ifdef CONFIG_WPS
+       if (wpas_wps_in_progress(wpa_s)) {
+               wpa_printf(MSG_DEBUG, "WPS: Order scan results with WPS "
+                          "provisioning rules");
+               compar = wpa_scan_result_wps_compar;
+       }
+#endif /* CONFIG_WPS */
+
+       qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
+             compar);
+
+       wpa_bss_update_start(wpa_s);
+       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;
+}
+
+
+void wpa_scan_results_free(struct wpa_scan_results *res)
+{
+       size_t i;
+
+       if (res == NULL)
+               return;
+
+       for (i = 0; i < res->num; i++)
+               os_free(res->res[i]);
+       os_free(res->res);
+       os_free(res);
+}