wpa_supplicant: Initial Revision 0.8.X

Based on:
commit 0725cc7b7efc434910e89865c42eda7ce61bbf08
Author: Jouni Malinen <j@w1.fi>
Date:   Thu Apr 21 20:41:01 2011 +0300

    Enable CONFIG_DRIVER_NL80211=y in the default configuration

    nl80211 should be preferred over WEXT with any recent Linux
    kernel version.

Change-Id: I26aec5afbbd4f4a1f5fd900912545b6f5050de64
Signed-off-by: Dmitry Shmidt <dimitrysh@google.com>

1 files changed, 840 insertions, 0 deletions

diff --git a/wpa_supplicant/scan.c b/wpa_supplicant/scan.c
new file mode 100644
index 0000000..4fb9bef
--- /dev/null
+++ b/wpa_supplicant/scan.c
@@ -0,0 +1,840 @@
+/*
+ * WPA Supplicant - Scanning
+ * 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
+ * published by the Free Software Foundation.
+ *
+ * Alternatively, this software may be distributed under the terms of BSD
+ * license.
+ *
+ * See README and COPYING for more details.
+ */
+
+#include "utils/includes.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)
+{
+	struct wpa_ssid *ssid;
+	union wpa_event_data data;
+
+	ssid = wpa_supplicant_get_ssid(wpa_s);
+	if (ssid == NULL)
+		return;
+
+	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_dbg(wpa_s, MSG_DEBUG, "Already associated with a configured "
+		"network - generating associated event");
+	os_memset(&data, 0, sizeof(data));
+	wpa_supplicant_event(wpa_s, EVENT_ASSOC, &data);
+}
+
+
+#ifdef CONFIG_WPS
+static int wpas_wps_in_use(struct wpa_config *conf,
+			   enum wps_request_type *req_type)
+{
+	struct wpa_ssid *ssid;
+	int wps = 0;
+
+	for (ssid = conf->ssid; ssid; ssid = ssid->next) {
+		if (!(ssid->key_mgmt & WPA_KEY_MGMT_WPS))
+			continue;
+
+		wps = 1;
+		*req_type = wpas_wps_get_req_type(ssid);
+		if (!ssid->eap.phase1)
+			continue;
+
+		if (os_strstr(ssid->eap.phase1, "pbc=1"))
+			return 2;
+	}
+
+	return wps;
+}
+#endif /* CONFIG_WPS */
+
+
+int wpa_supplicant_enabled_networks(struct wpa_config *conf)
+{
+	struct wpa_ssid *ssid = conf->ssid;
+	int count = 0;
+	while (ssid) {
+		if (!ssid->disabled)
+			count++;
+		ssid = ssid->next;
+	}
+	return count;
+}
+
+
+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_dbg(wpa_s, MSG_DEBUG, "wpa_supplicant_assoc_try: 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 scan_req = 0, ret;
+	struct wpabuf *wps_ie = NULL;
+#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->wpa_state == WPA_INTERFACE_DISABLED) {
+		wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
+		return;
+	}
+
+	if (wpa_s->disconnected && !wpa_s->scan_req) {
+		wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
+		return;
+	}
+
+	if (!wpa_supplicant_enabled_networks(wpa_s->conf) &&
+	    !wpa_s->scan_req) {
+		wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks - do not scan");
+		wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
+		return;
+	}
+
+	if (wpa_s->conf->ap_scan != 0 &&
+	    (wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
+		wpa_dbg(wpa_s, 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) {
+		wpa_supplicant_gen_assoc_event(wpa_s);
+		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 != WILDCARD_SSID_SCAN) {
+		while (ssid) {
+			if (ssid == wpa_s->prev_scan_ssid) {
+				ssid = ssid->next;
+				break;
+			}
+			ssid = ssid->next;
+		}
+	}
+
+	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) {
+		/*
+		 * User-initiated scan request in ap_scan == 2; scan with
+		 * wildcard SSID.
+		 */
+		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;
+		}
+
+		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;
+		}
+		int_array_sort_unique(params.freqs);
+	}
+
+	if (ssid) {
+		wpa_s->prev_scan_ssid = ssid;
+		if (max_ssids > 1) {
+			wpa_dbg(wpa_s, MSG_DEBUG, "Include wildcard SSID in "
+				"the scan request");
+			params.num_ssids++;
+		}
+		wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for specific "
+			"SSID(s)");
+	} else {
+		wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
+		params.num_ssids++;
+		wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
+			"SSID");
+	}
+
+#ifdef CONFIG_P2P
+	wpa_s->wps->dev.p2p = 1;
+	if (!wps) {
+		wps = 1;
+		req_type = WPS_REQ_ENROLLEE_INFO;
+	}
+
+	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_dbg(wpa_s, 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->p2p_in_provisioning < 8 &&
+			   wpa_s->go_params->freq_list[0]) {
+			wpa_dbg(wpa_s, 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_dbg(wpa_s, 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,
+						0, NULL);
+		if (wps_ie) {
+			params.extra_ies = wpabuf_head(wps_ie);
+			params.extra_ies_len = wpabuf_len(wps_ie);
+		}
+	}
+#endif /* CONFIG_WPS */
+
+#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 */
+
+	if (params.freqs == NULL && wpa_s->next_scan_freqs) {
+		wpa_dbg(wpa_s, MSG_DEBUG, "Optimize scan based on previously "
+			"generated frequency list");
+		params.freqs = wpa_s->next_scan_freqs;
+	} else
+		os_free(wpa_s->next_scan_freqs);
+	wpa_s->next_scan_freqs = NULL;
+
+	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_msg(wpa_s, MSG_WARNING, "Failed to initiate AP scan");
+		if (prev_state != wpa_s->wpa_state)
+			wpa_supplicant_set_state(wpa_s, prev_state);
+		wpa_supplicant_req_scan(wpa_s, 1, 0);
+	}
+}
+
+
+/**
+ * wpa_supplicant_req_scan - Schedule a scan for neighboring access points
+ * @wpa_s: Pointer to wpa_supplicant data
+ * @sec: Number of seconds after which to scan
+ * @usec: Number of microseconds after which to scan
+ *
+ * This function is used to schedule a scan for neighboring access points after
+ * the specified time.
+ */
+void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
+{
+	/* If there's at least one network that should be specifically scanned
+	 * then don't cancel the scan and reschedule.  Some drivers do
+	 * background scanning which generates frequent scan results, and that
+	 * causes the specific SSID scan to get continually pushed back and
+	 * never happen, which causes hidden APs to never get probe-scanned.
+	 */
+	if (eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL) &&
+	    wpa_s->conf->ap_scan == 1) {
+		struct wpa_ssid *ssid = wpa_s->conf->ssid;
+
+		while (ssid) {
+			if (!ssid->disabled && ssid->scan_ssid)
+				break;
+			ssid = ssid->next;
+		}
+		if (ssid) {
+			wpa_dbg(wpa_s, MSG_DEBUG, "Not rescheduling scan to "
+			        "ensure that specific SSID scans occur");
+			return;
+		}
+	}
+
+	wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec",
+		sec, usec);
+	eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
+	eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
+}
+
+
+/**
+ * wpa_supplicant_cancel_scan - Cancel a scheduled scan request
+ * @wpa_s: Pointer to wpa_supplicant data
+ *
+ * This function is used to cancel a scan request scheduled with
+ * wpa_supplicant_req_scan().
+ */
+void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
+{
+	wpa_dbg(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_dbg(wpa_s, MSG_DEBUG, "Failed to get scan results");
+		return NULL;
+	}
+
+#ifdef CONFIG_WPS
+	if (wpas_wps_in_progress(wpa_s)) {
+		wpa_dbg(wpa_s, 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);
+}