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>
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(¶ms, 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(¶ms.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(¶ms.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, ¶ms.num_filter_ssids);
+
+ ret = wpa_supplicant_trigger_scan(wpa_s, ¶ms);
+
+ 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);
+}