[thirdparty/hostap.git] / wpa_supplicant / bss.c

/*
 * BSS table
 * Copyright (c) 2009-2010, 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 "drivers/driver.h"
#include "wpa_supplicant_i.h"
#include "notify.h"
#include "scan.h"
#include "bss.h"


#ifndef WPA_BSS_MAX_COUNT
#define WPA_BSS_MAX_COUNT 200
#endif /* WPA_BSS_MAX_COUNT */

/**
 * WPA_BSS_EXPIRATION_PERIOD - Period of expiration run in seconds
 */
#define WPA_BSS_EXPIRATION_PERIOD 10

/**
 * WPA_BSS_EXPIRATION_AGE - BSS entry age after which it can be expired
 *
 * This value control the time in seconds after which a BSS entry gets removed
 * if it has not been updated or is not in use.
 */
#define WPA_BSS_EXPIRATION_AGE 180

/**
 * WPA_BSS_EXPIRATION_SCAN_COUNT - Expire BSS after number of scans
 *
 * If the BSS entry has not been seen in this many scans, it will be removed.
 * Value 1 means that the entry is removed after the first scan without the
 * BSSID being seen. Larger values can be used to avoid BSS entries
 * disappearing if they are not visible in every scan (e.g., low signal quality
 * or interference).
 */
#define WPA_BSS_EXPIRATION_SCAN_COUNT 2


static void wpa_bss_remove(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
{
	dl_list_del(&bss->list);
	dl_list_del(&bss->list_id);
	wpa_s->num_bss--;
	wpa_printf(MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR " SSID '%s'",
		   bss->id, MAC2STR(bss->bssid),
		   wpa_ssid_txt(bss->ssid, bss->ssid_len));
	wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id);
	os_free(bss);
}


struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid,
			     const u8 *ssid, size_t ssid_len)
{
	struct wpa_bss *bss;
	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
		if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
		    bss->ssid_len == ssid_len &&
		    os_memcmp(bss->ssid, ssid, ssid_len) == 0)
			return bss;
	}
	return NULL;
}


static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src)
{
	os_time_t usec;

	dst->flags = src->flags;
	os_memcpy(dst->bssid, src->bssid, ETH_ALEN);
	dst->freq = src->freq;
	dst->beacon_int = src->beacon_int;
	dst->caps = src->caps;
	dst->qual = src->qual;
	dst->noise = src->noise;
	dst->level = src->level;
	dst->tsf = src->tsf;

	os_get_time(&dst->last_update);
	dst->last_update.sec -= src->age / 1000;
	usec = (src->age % 1000) * 1000;
	if (dst->last_update.usec < usec) {
		dst->last_update.sec--;
		dst->last_update.usec += 1000000;
	}
	dst->last_update.usec -= usec;
}


static void wpa_bss_add(struct wpa_supplicant *wpa_s,
			const u8 *ssid, size_t ssid_len,
			struct wpa_scan_res *res)
{
	struct wpa_bss *bss;

	bss = os_zalloc(sizeof(*bss) + res->ie_len);
	if (bss == NULL)
		return;
	bss->id = wpa_s->bss_next_id++;
	bss->last_update_idx = wpa_s->bss_update_idx;
	wpa_bss_copy_res(bss, res);
	os_memcpy(bss->ssid, ssid, ssid_len);
	bss->ssid_len = ssid_len;
	bss->ie_len = res->ie_len;
	os_memcpy(bss + 1, res + 1, res->ie_len);

	dl_list_add_tail(&wpa_s->bss, &bss->list);
	dl_list_add_tail(&wpa_s->bss_id, &bss->list_id);
	wpa_s->num_bss++;
	wpa_printf(MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR " SSID '%s'",
		   bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len));
	wpas_notify_bss_added(wpa_s, bss->bssid, bss->id);
	if (wpa_s->num_bss > WPA_BSS_MAX_COUNT) {
		/* Remove the oldest entry */
		wpa_bss_remove(wpa_s, dl_list_first(&wpa_s->bss,
						    struct wpa_bss, list));
	}
}


static void wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
			   struct wpa_scan_res *res)
{
	bss->scan_miss_count = 0;
	bss->last_update_idx = wpa_s->bss_update_idx;
	wpa_bss_copy_res(bss, res);
	/* Move the entry to the end of the list */
	dl_list_del(&bss->list);
	if (bss->ie_len >= res->ie_len) {
		os_memcpy(bss + 1, res + 1, res->ie_len);
		bss->ie_len = res->ie_len;
	} else {
		struct wpa_bss *nbss;
		struct dl_list *prev = bss->list_id.prev;
		dl_list_del(&bss->list_id);
		nbss = os_realloc(bss, sizeof(*bss) + res->ie_len);
		if (nbss) {
			bss = nbss;
			os_memcpy(bss + 1, res + 1, res->ie_len);
			bss->ie_len = res->ie_len;
		}
		dl_list_add(prev, &bss->list_id);
	}
	dl_list_add_tail(&wpa_s->bss, &bss->list);
}


static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
{
	return bss == wpa_s->current_bss ||
		os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 ||
		os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0;
}


void wpa_bss_update_start(struct wpa_supplicant *wpa_s)
{
	wpa_s->bss_update_idx++;
	wpa_printf(MSG_DEBUG, "BSS: Start scan result update %u",
		   wpa_s->bss_update_idx);
}


void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s,
			     struct wpa_scan_res *res)
{
	const u8 *ssid;
	struct wpa_bss *bss;

	ssid = wpa_scan_get_ie(res, WLAN_EID_SSID);
	if (ssid == NULL) {
		wpa_printf(MSG_DEBUG, "BSS: No SSID IE included for " MACSTR,
			   MAC2STR(res->bssid));
		return;
	}
	if (ssid[1] > 32) {
		wpa_printf(MSG_DEBUG, "BSS: Too long SSID IE included for "
			   MACSTR, MAC2STR(res->bssid));
		return;
	}

	/* TODO: add option for ignoring BSSes we are not interested in
	 * (to save memory) */
	bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]);
	if (bss == NULL)
		wpa_bss_add(wpa_s, ssid + 2, ssid[1], res);
	else
		wpa_bss_update(wpa_s, bss, res);
}


static int wpa_bss_included_in_scan(const struct wpa_bss *bss,
				    const struct scan_info *info)
{
	int found;
	size_t i;

	if (info == NULL)
		return 1;

	if (info->num_freqs) {
		found = 0;
		for (i = 0; i < info->num_freqs; i++) {
			if (bss->freq == info->freqs[i]) {
				found = 1;
				break;
			}
		}
		if (!found)
			return 0;
	}

	if (info->num_ssids) {
		found = 0;
		for (i = 0; i < info->num_ssids; i++) {
			const struct wpa_driver_scan_ssid *s = &info->ssids[i];
			if ((s->ssid == NULL || s->ssid_len == 0) ||
			    (s->ssid_len == bss->ssid_len &&
			     os_memcmp(s->ssid, bss->ssid, bss->ssid_len) ==
			     0)) {
				found = 1;
				break;
			}
		}
		if (!found)
			return 0;
	}

	return 1;
}


void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info,
			int new_scan)
{
	struct wpa_bss *bss, *n;

	if (!new_scan)
		return; /* do not expire entries without new scan */

	dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
		if (wpa_bss_in_use(wpa_s, bss))
			continue;
		if (!wpa_bss_included_in_scan(bss, info))
			continue; /* expire only BSSes that were scanned */
		if (bss->last_update_idx < wpa_s->bss_update_idx)
			bss->scan_miss_count++;
		if (bss->scan_miss_count >= WPA_BSS_EXPIRATION_SCAN_COUNT) {
			wpa_printf(MSG_DEBUG, "BSS: Expire BSS %u due to no "
				   "match in scan", bss->id);
			wpa_bss_remove(wpa_s, bss);
		}
	}
}


static void wpa_bss_timeout(void *eloop_ctx, void *timeout_ctx)
{
	struct wpa_supplicant *wpa_s = eloop_ctx;
	struct wpa_bss *bss, *n;
	struct os_time t;

	if (dl_list_empty(&wpa_s->bss))
		return;

	os_get_time(&t);
	t.sec -= WPA_BSS_EXPIRATION_AGE;

	dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
		if (wpa_bss_in_use(wpa_s, bss))
			continue;

		if (os_time_before(&bss->last_update, &t)) {
			wpa_printf(MSG_DEBUG, "BSS: Expire BSS %u due to age",
				   bss->id);
			wpa_bss_remove(wpa_s, bss);
		} else
			break;
	}
	eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
			       wpa_bss_timeout, wpa_s, NULL);
}


int wpa_bss_init(struct wpa_supplicant *wpa_s)
{
	dl_list_init(&wpa_s->bss);
	dl_list_init(&wpa_s->bss_id);
	eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
			       wpa_bss_timeout, wpa_s, NULL);
	return 0;
}


void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
{
	struct wpa_bss *bss, *n;
	eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL);
	if (wpa_s->bss.next == NULL)
		return; /* BSS table not yet initialized */
	dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list)
		wpa_bss_remove(wpa_s, bss);
}


struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
				   const u8 *bssid)
{
	struct wpa_bss *bss;
	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
		if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
			return bss;
	}
	return NULL;
}


struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id)
{
	struct wpa_bss *bss;
	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
		if (bss->id == id)
			return bss;
	}
	return NULL;
}


const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie)
{
	const u8 *end, *pos;

	pos = (const u8 *) (bss + 1);
	end = pos + bss->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_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type)
{
	const u8 *end, *pos;

	pos = (const u8 *) (bss + 1);
	end = pos + bss->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_bss_get_vendor_ie_multi(const struct wpa_bss *bss,
					    u32 vendor_type)
{
	struct wpabuf *buf;
	const u8 *end, *pos;

	buf = wpabuf_alloc(bss->ie_len);
	if (buf == NULL)
		return NULL;

	pos = (const u8 *) (bss + 1);
	end = pos + bss->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;
}


int wpa_bss_get_max_rate(const struct wpa_bss *bss)
{
	int rate = 0;
	const u8 *ie;
	int i;

	ie = wpa_bss_get_ie(bss, 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_bss_get_ie(bss, 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;
}
Commit	Line	Data
83922c2d JM	1	/*
83922c2d JM	2	* BSS table
8d923a4a	3	* Copyright (c) 2009-2010, Jouni Malinen <j@w1.fi>
83922c2d JM	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License version 2 as
	7	* published by the Free Software Foundation.
	8	*
	9	* Alternatively, this software may be distributed under the terms of BSD
	10	* license.
	11	*
	12	* See README and COPYING for more details.
	13	*/
	14
	15	#include "utils/includes.h"
	16
	17	#include "utils/common.h"
	18	#include "utils/eloop.h"
	19	#include "common/ieee802_11_defs.h"
	20	#include "drivers/driver.h"
	21	#include "wpa_supplicant_i.h"
	22	#include "notify.h"
d1f9c410	23	#include "scan.h"
83922c2d JM	24	#include "bss.h"
	25
	26
	27	#ifndef WPA_BSS_MAX_COUNT
	28	#define WPA_BSS_MAX_COUNT 200
	29	#endif /* WPA_BSS_MAX_COUNT */
	30
	31	/**
	32	* WPA_BSS_EXPIRATION_PERIOD - Period of expiration run in seconds
	33	*/
	34	#define WPA_BSS_EXPIRATION_PERIOD 10
	35
	36	/**
	37	* WPA_BSS_EXPIRATION_AGE - BSS entry age after which it can be expired
	38	*
	39	* This value control the time in seconds after which a BSS entry gets removed
	40	* if it has not been updated or is not in use.
	41	*/
	42	#define WPA_BSS_EXPIRATION_AGE 180
	43
	44	/**
	45	* WPA_BSS_EXPIRATION_SCAN_COUNT - Expire BSS after number of scans
	46	*
	47	* If the BSS entry has not been seen in this many scans, it will be removed.
	48	* Value 1 means that the entry is removed after the first scan without the
	49	* BSSID being seen. Larger values can be used to avoid BSS entries
	50	* disappearing if they are not visible in every scan (e.g., low signal quality
	51	* or interference).
	52	*/
	53	#define WPA_BSS_EXPIRATION_SCAN_COUNT 2
	54
	55
	56	static void wpa_bss_remove(struct wpa_supplicant wpa_s, struct wpa_bss bss)
	57	{
	58	dl_list_del(&bss->list);
d4bf8f13	59	dl_list_del(&bss->list_id);
83922c2d JM	60	wpa_s->num_bss--;
	61	wpa_printf(MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR " SSID '%s'",
	62	bss->id, MAC2STR(bss->bssid),
	63	wpa_ssid_txt(bss->ssid, bss->ssid_len));
f0d126d3	64	wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id);
83922c2d JM	65	os_free(bss);
	66	}
	67
	68
59f2caa9 JM	69	struct wpa_bss * wpa_bss_get(struct wpa_supplicant wpa_s, const u8 bssid,
59f2caa9 JM	70	const u8 *ssid, size_t ssid_len)
83922c2d JM	71	{
	72	struct wpa_bss *bss;
	73	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
	74	if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
	75	bss->ssid_len == ssid_len &&
	76	os_memcmp(bss->ssid, ssid, ssid_len) == 0)
	77	return bss;
	78	}
	79	return NULL;
	80	}
	81
	82
	83	static void wpa_bss_copy_res(struct wpa_bss dst, struct wpa_scan_res src)
	84	{
	85	os_time_t usec;
	86
	87	dst->flags = src->flags;
	88	os_memcpy(dst->bssid, src->bssid, ETH_ALEN);
	89	dst->freq = src->freq;
	90	dst->beacon_int = src->beacon_int;
	91	dst->caps = src->caps;
	92	dst->qual = src->qual;
	93	dst->noise = src->noise;
	94	dst->level = src->level;
	95	dst->tsf = src->tsf;
	96
	97	os_get_time(&dst->last_update);
	98	dst->last_update.sec -= src->age / 1000;
	99	usec = (src->age % 1000) * 1000;
	100	if (dst->last_update.usec < usec) {
	101	dst->last_update.sec--;
	102	dst->last_update.usec += 1000000;
	103	}
	104	dst->last_update.usec -= usec;
	105	}
	106
	107
	108	static void wpa_bss_add(struct wpa_supplicant *wpa_s,
	109	const u8 *ssid, size_t ssid_len,
	110	struct wpa_scan_res *res)
	111	{
	112	struct wpa_bss *bss;
	113
	114	bss = os_zalloc(sizeof(*bss) + res->ie_len);
	115	if (bss == NULL)
	116	return;
	117	bss->id = wpa_s->bss_next_id++;
	118	bss->last_update_idx = wpa_s->bss_update_idx;
	119	wpa_bss_copy_res(bss, res);
	120	os_memcpy(bss->ssid, ssid, ssid_len);
	121	bss->ssid_len = ssid_len;
	122	bss->ie_len = res->ie_len;
	123	os_memcpy(bss + 1, res + 1, res->ie_len);
	124
	125	dl_list_add_tail(&wpa_s->bss, &bss->list);
d4bf8f13	126	dl_list_add_tail(&wpa_s->bss_id, &bss->list_id);
83922c2d JM	127	wpa_s->num_bss++;
	128	wpa_printf(MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR " SSID '%s'",
	129	bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len));
f0d126d3	130	wpas_notify_bss_added(wpa_s, bss->bssid, bss->id);
83922c2d JM	131	if (wpa_s->num_bss > WPA_BSS_MAX_COUNT) {
	132	/* Remove the oldest entry */
	133	wpa_bss_remove(wpa_s, dl_list_first(&wpa_s->bss,
	134	struct wpa_bss, list));
	135	}
	136	}
	137
	138
	139	static void wpa_bss_update(struct wpa_supplicant wpa_s, struct wpa_bss bss,
	140	struct wpa_scan_res *res)
	141	{
	142	bss->scan_miss_count = 0;
	143	bss->last_update_idx = wpa_s->bss_update_idx;
	144	wpa_bss_copy_res(bss, res);
	145	/* Move the entry to the end of the list */
	146	dl_list_del(&bss->list);
	147	if (bss->ie_len >= res->ie_len) {
	148	os_memcpy(bss + 1, res + 1, res->ie_len);
	149	bss->ie_len = res->ie_len;
	150	} else {
	151	struct wpa_bss *nbss;
1c83b67e JM	152	struct dl_list *prev = bss->list_id.prev;
1c83b67e JM	153	dl_list_del(&bss->list_id);
83922c2d JM	154	nbss = os_realloc(bss, sizeof(*bss) + res->ie_len);
	155	if (nbss) {
	156	bss = nbss;
	157	os_memcpy(bss + 1, res + 1, res->ie_len);
	158	bss->ie_len = res->ie_len;
	159	}
1c83b67e	160	dl_list_add(prev, &bss->list_id);
83922c2d JM	161	}
	162	dl_list_add_tail(&wpa_s->bss, &bss->list);
	163	}
	164
	165
7d7d57b2 JM	166	static int wpa_bss_in_use(struct wpa_supplicant wpa_s, struct wpa_bss bss)
	167	{
	168	return bss == wpa_s->current_bss \|\|
	169	os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 \|\|
	170	os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0;
	171	}
	172
	173
83922c2d JM	174	void wpa_bss_update_start(struct wpa_supplicant *wpa_s)
	175	{
	176	wpa_s->bss_update_idx++;
	177	wpa_printf(MSG_DEBUG, "BSS: Start scan result update %u",
	178	wpa_s->bss_update_idx);
	179	}
	180
	181
	182	void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s,
	183	struct wpa_scan_res *res)
	184	{
	185	const u8 *ssid;
	186	struct wpa_bss *bss;
	187
	188	ssid = wpa_scan_get_ie(res, WLAN_EID_SSID);
	189	if (ssid == NULL) {
	190	wpa_printf(MSG_DEBUG, "BSS: No SSID IE included for " MACSTR,
	191	MAC2STR(res->bssid));
	192	return;
	193	}
	194	if (ssid[1] > 32) {
	195	wpa_printf(MSG_DEBUG, "BSS: Too long SSID IE included for "
	196	MACSTR, MAC2STR(res->bssid));
	197	return;
	198	}
	199
	200	/* TODO: add option for ignoring BSSes we are not interested in
	201	* (to save memory) */
	202	bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]);
	203	if (bss == NULL)
	204	wpa_bss_add(wpa_s, ssid + 2, ssid[1], res);
	205	else
	206	wpa_bss_update(wpa_s, bss, res);
	207	}
	208
	209
8d923a4a JM	210	static int wpa_bss_included_in_scan(const struct wpa_bss *bss,
	211	const struct scan_info *info)
	212	{
	213	int found;
	214	size_t i;
	215
	216	if (info == NULL)
	217	return 1;
	218
	219	if (info->num_freqs) {
	220	found = 0;
	221	for (i = 0; i < info->num_freqs; i++) {
	222	if (bss->freq == info->freqs[i]) {
	223	found = 1;
	224	break;
	225	}
	226	}
	227	if (!found)
	228	return 0;
	229	}
	230
	231	if (info->num_ssids) {
	232	found = 0;
	233	for (i = 0; i < info->num_ssids; i++) {
	234	const struct wpa_driver_scan_ssid *s = &info->ssids[i];
	235	if ((s->ssid == NULL \|\| s->ssid_len == 0) \|\|
	236	(s->ssid_len == bss->ssid_len &&
	237	os_memcmp(s->ssid, bss->ssid, bss->ssid_len) ==
	238	0)) {
	239	found = 1;
	240	break;
	241	}
	242	}
	243	if (!found)
	244	return 0;
	245	}
	246
	247	return 1;
	248	}
	249
	250
	251	void wpa_bss_update_end(struct wpa_supplicant wpa_s, struct scan_info info,
	252	int new_scan)
83922c2d JM	253	{
	254	struct wpa_bss bss, n;
	255
8d923a4a JM	256	if (!new_scan)
8d923a4a JM	257	return; /* do not expire entries without new scan */
83922c2d JM	258
83922c2d JM	259	dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
7d7d57b2 JM	260	if (wpa_bss_in_use(wpa_s, bss))
7d7d57b2 JM	261	continue;
8d923a4a JM	262	if (!wpa_bss_included_in_scan(bss, info))
8d923a4a JM	263	continue; /* expire only BSSes that were scanned */
83922c2d JM	264	if (bss->last_update_idx < wpa_s->bss_update_idx)
	265	bss->scan_miss_count++;
	266	if (bss->scan_miss_count >= WPA_BSS_EXPIRATION_SCAN_COUNT) {
	267	wpa_printf(MSG_DEBUG, "BSS: Expire BSS %u due to no "
	268	"match in scan", bss->id);
	269	wpa_bss_remove(wpa_s, bss);
	270	}
	271	}
	272	}
	273
	274
	275	static void wpa_bss_timeout(void eloop_ctx, void timeout_ctx)
	276	{
	277	struct wpa_supplicant *wpa_s = eloop_ctx;
	278	struct wpa_bss bss, n;
	279	struct os_time t;
	280
	281	if (dl_list_empty(&wpa_s->bss))
	282	return;
	283
	284	os_get_time(&t);
	285	t.sec -= WPA_BSS_EXPIRATION_AGE;
	286
	287	dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
7d7d57b2 JM	288	if (wpa_bss_in_use(wpa_s, bss))
7d7d57b2 JM	289	continue;
83922c2d JM	290
	291	if (os_time_before(&bss->last_update, &t)) {
	292	wpa_printf(MSG_DEBUG, "BSS: Expire BSS %u due to age",
	293	bss->id);
	294	wpa_bss_remove(wpa_s, bss);
	295	} else
	296	break;
	297	}
	298	eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
	299	wpa_bss_timeout, wpa_s, NULL);
	300	}
	301
	302
	303	int wpa_bss_init(struct wpa_supplicant *wpa_s)
	304	{
	305	dl_list_init(&wpa_s->bss);
d4bf8f13	306	dl_list_init(&wpa_s->bss_id);
83922c2d JM	307	eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
	308	wpa_bss_timeout, wpa_s, NULL);
	309	return 0;
	310	}
	311
	312
	313	void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
	314	{
	315	struct wpa_bss bss, n;
	316	eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL);
e5fc8c8c JM	317	if (wpa_s->bss.next == NULL)
e5fc8c8c JM	318	return; /* BSS table not yet initialized */
83922c2d JM	319	dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list)
	320	wpa_bss_remove(wpa_s, bss);
	321	}
d4bf8f13 JM	322
	323
	324	struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
	325	const u8 *bssid)
	326	{
	327	struct wpa_bss *bss;
	328	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
	329	if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
	330	return bss;
	331	}
	332	return NULL;
	333	}
	334
	335
	336	struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id)
	337	{
	338	struct wpa_bss *bss;
	339	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
	340	if (bss->id == id)
	341	return bss;
	342	}
	343	return NULL;
	344	}
	345
	346
	347	const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie)
	348	{
	349	const u8 end, pos;
	350
	351	pos = (const u8 *) (bss + 1);
	352	end = pos + bss->ie_len;
	353
	354	while (pos + 1 < end) {
	355	if (pos + 2 + pos[1] > end)
	356	break;
	357	if (pos[0] == ie)
	358	return pos;
	359	pos += 2 + pos[1];
	360	}
	361
	362	return NULL;
	363	}
	364
	365
	366	const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type)
	367	{
	368	const u8 end, pos;
	369
	370	pos = (const u8 *) (bss + 1);
	371	end = pos + bss->ie_len;
	372
	373	while (pos + 1 < end) {
	374	if (pos + 2 + pos[1] > end)
	375	break;
	376	if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
	377	vendor_type == WPA_GET_BE32(&pos[2]))
	378	return pos;
	379	pos += 2 + pos[1];
	380	}
	381
	382	return NULL;
	383	}
	384
	385
386	struct wpabuf * wpa_bss_get_vendor_ie_multi(const struct wpa_bss *bss,
387	u32 vendor_type)
388	{
389	struct wpabuf *buf;
390	const u8 end, pos;
391
392	buf = wpabuf_alloc(bss->ie_len);
393	if (buf == NULL)
394	return NULL;
395
396	pos = (const u8 *) (bss + 1);
397	end = pos + bss->ie_len;
398
399	while (pos + 1 < end) {
400	if (pos + 2 + pos[1] > end)
401	break;
402	if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
403	vendor_type == WPA_GET_BE32(&pos[2]))
404	wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
405	pos += 2 + pos[1];
406	}
407
408	if (wpabuf_len(buf) == 0) {
409	wpabuf_free(buf);
410	buf = NULL;
411	}
412
413	return buf;
414	}
99a6a63f JM	415
	416
	417	int wpa_bss_get_max_rate(const struct wpa_bss *bss)
	418	{
	419	int rate = 0;
	420	const u8 *ie;
	421	int i;
	422
	423	ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
	424	for (i = 0; ie && i < ie[1]; i++) {
	425	if ((ie[i + 2] & 0x7f) > rate)
	426	rate = ie[i + 2] & 0x7f;
	427	}
	428
	429	ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
	430	for (i = 0; ie && i < ie[1]; i++) {
	431	if ((ie[i + 2] & 0x7f) > rate)
	432	rate = ie[i + 2] & 0x7f;
	433	}
	434
	435	return rate;
	436	}