wpa_supplicant/scan.c - platform/external/wpa_supplicant_6 - Git at Google

 /*
  * WPA Supplicant - Scanning
  * Copyright (c) 2003-2008, Jouni Malinen <[email protected]>
  *
  * 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 "includes.h"

 #include "common.h"
 #include "eloop.h"
 #include "config.h"
 #include "wpa_supplicant_i.h"
 #include "mlme.h"
 #include "wps_supplicant.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;
 	wpa_supplicant_initiate_eapol(wpa_s);
 	wpa_printf(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 */

 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;
 	struct wpabuf *wps_ie = NULL;
 	const u8 *extra_ie = NULL;
 	size_t extra_ie_len = 0;
 	int wps = 0;
 #ifdef CONFIG_WPS
 	enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
 #endif /* CONFIG_WPS */

 	if (wpa_s->disconnected && !wpa_s->scan_req)
 		return;

 	enabled = 0;
 	ssid = wpa_s->conf->ssid;
 	while (ssid) {
 		if (!ssid->disabled) {
 			enabled++;
 			break;
 		}
 		ssid = ssid->next;
 	}
 	if (!enabled && !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_printf(MSG_DEBUG, "Using wired authentication - "
 			   "overriding ap_scan configuration");
 		wpa_s->conf->ap_scan = 0;
 	}

 	if (wpa_s->conf->ap_scan == 0) {
 		wpa_supplicant_gen_assoc_event(wpa_s);
 		return;
 	}

 	if (wpa_s->wpa_state == WPA_DISCONNECTED ||
 	    wpa_s->wpa_state == WPA_INACTIVE)
 		wpa_supplicant_set_state(wpa_s, WPA_SCANNING);

 	ssid = wpa_s->conf->ssid;
 	if (wpa_s->prev_scan_ssid != BROADCAST_SSID_SCAN) {
 		while (ssid) {
 			if (ssid == wpa_s->prev_scan_ssid) {
 				ssid = ssid->next;
 				break;
 			}
 			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) {
 		/*
 		 * ap_scan=2 mode - try to associate with each SSID instead of
 		 * scanning for each scan_ssid=1 network.
 		 */
 		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;
 		}
 		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;
 		}
 		wpa_supplicant_associate(wpa_s, NULL, ssid);
 		return;
 	}

 	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;

 #ifdef CONFIG_WPS
 	wps = wpas_wps_in_use(wpa_s->conf, &req_type);
 #endif /* CONFIG_WPS */

 	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;
 	}

 #ifdef CONFIG_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);
 		}
 	}
 #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);
 	}

 	wpabuf_free(wps_ie);

 	if (ret) {
 		wpa_printf(MSG_WARNING, "Failed to initiate AP scan.");
 		wpa_supplicant_req_scan(wpa_s, 10, 0);
 	} else {
 		wpa_s->scan_runs++;
 		wpa_s->scan_ongoing = 1;
 	}
 }


 /**
  * 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)
 {
 #ifndef ANDROID
 	/* 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_msg(wpa_s, MSG_DEBUG, "Not rescheduling scan to "
 			        "ensure that specific SSID scans occur");
 			return;
 		}
 	}
 #endif

 	wpa_msg(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_msg(wpa_s, MSG_DEBUG, "Cancelling scan request");
 	eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
 }
	/*
	* WPA Supplicant - Scanning
	* Copyright (c) 2003-2008, Jouni Malinen <[email protected]>
	*
	* 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 "includes.h"

	#include "common.h"
	#include "eloop.h"
	#include "config.h"
	#include "wpa_supplicant_i.h"
	#include "mlme.h"
	#include "wps_supplicant.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;
	wpa_supplicant_initiate_eapol(wpa_s);
	wpa_printf(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 */

	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;
	struct wpabuf *wps_ie = NULL;
	const u8 *extra_ie = NULL;
	size_t extra_ie_len = 0;
	int wps = 0;
	#ifdef CONFIG_WPS
	enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
	#endif /* CONFIG_WPS */

	if (wpa_s->disconnected && !wpa_s->scan_req)
	return;

	enabled = 0;
	ssid = wpa_s->conf->ssid;
	while (ssid) {
	if (!ssid->disabled) {
	enabled++;
	break;
	}
	ssid = ssid->next;
	}
	if (!enabled && !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_printf(MSG_DEBUG, "Using wired authentication - "
	"overriding ap_scan configuration");
	wpa_s->conf->ap_scan = 0;
	}

	if (wpa_s->conf->ap_scan == 0) {
	wpa_supplicant_gen_assoc_event(wpa_s);
	return;
	}

	if (wpa_s->wpa_state == WPA_DISCONNECTED \|\|
	wpa_s->wpa_state == WPA_INACTIVE)
	wpa_supplicant_set_state(wpa_s, WPA_SCANNING);

	ssid = wpa_s->conf->ssid;
	if (wpa_s->prev_scan_ssid != BROADCAST_SSID_SCAN) {
	while (ssid) {
	if (ssid == wpa_s->prev_scan_ssid) {
	ssid = ssid->next;
	break;
	}
	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) {
	/*
	* ap_scan=2 mode - try to associate with each SSID instead of
	* scanning for each scan_ssid=1 network.
	*/
	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;
	}
	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;
	}
	wpa_supplicant_associate(wpa_s, NULL, ssid);
	return;
	}

	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;

	#ifdef CONFIG_WPS
	wps = wpas_wps_in_use(wpa_s->conf, &req_type);
	#endif /* CONFIG_WPS */

	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;
	}

	#ifdef CONFIG_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);
	}
	}
	#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);
	}

	wpabuf_free(wps_ie);

	if (ret) {
	wpa_printf(MSG_WARNING, "Failed to initiate AP scan.");
	wpa_supplicant_req_scan(wpa_s, 10, 0);
	} else {
	wpa_s->scan_runs++;
	wpa_s->scan_ongoing = 1;
	}
	}


	/**
	* 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)
	{
	#ifndef ANDROID
	/* 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_msg(wpa_s, MSG_DEBUG, "Not rescheduling scan to "
	"ensure that specific SSID scans occur");
	return;
	}
	}
	#endif

	wpa_msg(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_msg(wpa_s, MSG_DEBUG, "Cancelling scan request");
	eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
	}