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      1 /*
      2  * BSS table
      3  * Copyright (c) 2009-2015, Jouni Malinen <j (at) w1.fi>
      4  *
      5  * This software may be distributed under the terms of the BSD license.
      6  * See README for more details.
      7  */
      8 
      9 #include "utils/includes.h"
     10 
     11 #include "utils/common.h"
     12 #include "utils/eloop.h"
     13 #include "common/ieee802_11_defs.h"
     14 #include "drivers/driver.h"
     15 #include "wpa_supplicant_i.h"
     16 #include "config.h"
     17 #include "notify.h"
     18 #include "scan.h"
     19 #include "bss.h"
     20 
     21 
     22 #define WPA_BSS_FREQ_CHANGED_FLAG	BIT(0)
     23 #define WPA_BSS_SIGNAL_CHANGED_FLAG	BIT(1)
     24 #define WPA_BSS_PRIVACY_CHANGED_FLAG	BIT(2)
     25 #define WPA_BSS_MODE_CHANGED_FLAG	BIT(3)
     26 #define WPA_BSS_WPAIE_CHANGED_FLAG	BIT(4)
     27 #define WPA_BSS_RSNIE_CHANGED_FLAG	BIT(5)
     28 #define WPA_BSS_WPS_CHANGED_FLAG	BIT(6)
     29 #define WPA_BSS_RATES_CHANGED_FLAG	BIT(7)
     30 #define WPA_BSS_IES_CHANGED_FLAG	BIT(8)
     31 
     32 
     33 static void wpa_bss_set_hessid(struct wpa_bss *bss)
     34 {
     35 #ifdef CONFIG_INTERWORKING
     36 	const u8 *ie = wpa_bss_get_ie(bss, WLAN_EID_INTERWORKING);
     37 	if (ie == NULL || (ie[1] != 7 && ie[1] != 9)) {
     38 		os_memset(bss->hessid, 0, ETH_ALEN);
     39 		return;
     40 	}
     41 	if (ie[1] == 7)
     42 		os_memcpy(bss->hessid, ie + 3, ETH_ALEN);
     43 	else
     44 		os_memcpy(bss->hessid, ie + 5, ETH_ALEN);
     45 #endif /* CONFIG_INTERWORKING */
     46 }
     47 
     48 
     49 /**
     50  * wpa_bss_anqp_alloc - Allocate ANQP data structure for a BSS entry
     51  * Returns: Allocated ANQP data structure or %NULL on failure
     52  *
     53  * The allocated ANQP data structure has its users count set to 1. It may be
     54  * shared by multiple BSS entries and each shared entry is freed with
     55  * wpa_bss_anqp_free().
     56  */
     57 struct wpa_bss_anqp * wpa_bss_anqp_alloc(void)
     58 {
     59 	struct wpa_bss_anqp *anqp;
     60 	anqp = os_zalloc(sizeof(*anqp));
     61 	if (anqp == NULL)
     62 		return NULL;
     63 #ifdef CONFIG_INTERWORKING
     64 	dl_list_init(&anqp->anqp_elems);
     65 #endif /* CONFIG_INTERWORKING */
     66 	anqp->users = 1;
     67 	return anqp;
     68 }
     69 
     70 
     71 /**
     72  * wpa_bss_anqp_clone - Clone an ANQP data structure
     73  * @anqp: ANQP data structure from wpa_bss_anqp_alloc()
     74  * Returns: Cloned ANQP data structure or %NULL on failure
     75  */
     76 static struct wpa_bss_anqp * wpa_bss_anqp_clone(struct wpa_bss_anqp *anqp)
     77 {
     78 	struct wpa_bss_anqp *n;
     79 
     80 	n = os_zalloc(sizeof(*n));
     81 	if (n == NULL)
     82 		return NULL;
     83 
     84 #define ANQP_DUP(f) if (anqp->f) n->f = wpabuf_dup(anqp->f)
     85 #ifdef CONFIG_INTERWORKING
     86 	dl_list_init(&n->anqp_elems);
     87 	ANQP_DUP(capability_list);
     88 	ANQP_DUP(venue_name);
     89 	ANQP_DUP(network_auth_type);
     90 	ANQP_DUP(roaming_consortium);
     91 	ANQP_DUP(ip_addr_type_availability);
     92 	ANQP_DUP(nai_realm);
     93 	ANQP_DUP(anqp_3gpp);
     94 	ANQP_DUP(domain_name);
     95 #endif /* CONFIG_INTERWORKING */
     96 #ifdef CONFIG_HS20
     97 	ANQP_DUP(hs20_capability_list);
     98 	ANQP_DUP(hs20_operator_friendly_name);
     99 	ANQP_DUP(hs20_wan_metrics);
    100 	ANQP_DUP(hs20_connection_capability);
    101 	ANQP_DUP(hs20_operating_class);
    102 	ANQP_DUP(hs20_osu_providers_list);
    103 #endif /* CONFIG_HS20 */
    104 #undef ANQP_DUP
    105 
    106 	return n;
    107 }
    108 
    109 
    110 /**
    111  * wpa_bss_anqp_unshare_alloc - Unshare ANQP data (if shared) in a BSS entry
    112  * @bss: BSS entry
    113  * Returns: 0 on success, -1 on failure
    114  *
    115  * This function ensures the specific BSS entry has an ANQP data structure that
    116  * is not shared with any other BSS entry.
    117  */
    118 int wpa_bss_anqp_unshare_alloc(struct wpa_bss *bss)
    119 {
    120 	struct wpa_bss_anqp *anqp;
    121 
    122 	if (bss->anqp && bss->anqp->users > 1) {
    123 		/* allocated, but shared - clone an unshared copy */
    124 		anqp = wpa_bss_anqp_clone(bss->anqp);
    125 		if (anqp == NULL)
    126 			return -1;
    127 		anqp->users = 1;
    128 		bss->anqp->users--;
    129 		bss->anqp = anqp;
    130 		return 0;
    131 	}
    132 
    133 	if (bss->anqp)
    134 		return 0; /* already allocated and not shared */
    135 
    136 	/* not allocated - allocate a new storage area */
    137 	bss->anqp = wpa_bss_anqp_alloc();
    138 	return bss->anqp ? 0 : -1;
    139 }
    140 
    141 
    142 /**
    143  * wpa_bss_anqp_free - Free an ANQP data structure
    144  * @anqp: ANQP data structure from wpa_bss_anqp_alloc() or wpa_bss_anqp_clone()
    145  */
    146 static void wpa_bss_anqp_free(struct wpa_bss_anqp *anqp)
    147 {
    148 #ifdef CONFIG_INTERWORKING
    149 	struct wpa_bss_anqp_elem *elem;
    150 #endif /* CONFIG_INTERWORKING */
    151 
    152 	if (anqp == NULL)
    153 		return;
    154 
    155 	anqp->users--;
    156 	if (anqp->users > 0) {
    157 		/* Another BSS entry holds a pointer to this ANQP info */
    158 		return;
    159 	}
    160 
    161 #ifdef CONFIG_INTERWORKING
    162 	wpabuf_free(anqp->capability_list);
    163 	wpabuf_free(anqp->venue_name);
    164 	wpabuf_free(anqp->network_auth_type);
    165 	wpabuf_free(anqp->roaming_consortium);
    166 	wpabuf_free(anqp->ip_addr_type_availability);
    167 	wpabuf_free(anqp->nai_realm);
    168 	wpabuf_free(anqp->anqp_3gpp);
    169 	wpabuf_free(anqp->domain_name);
    170 
    171 	while ((elem = dl_list_first(&anqp->anqp_elems,
    172 				     struct wpa_bss_anqp_elem, list))) {
    173 		dl_list_del(&elem->list);
    174 		wpabuf_free(elem->payload);
    175 		os_free(elem);
    176 	}
    177 #endif /* CONFIG_INTERWORKING */
    178 #ifdef CONFIG_HS20
    179 	wpabuf_free(anqp->hs20_capability_list);
    180 	wpabuf_free(anqp->hs20_operator_friendly_name);
    181 	wpabuf_free(anqp->hs20_wan_metrics);
    182 	wpabuf_free(anqp->hs20_connection_capability);
    183 	wpabuf_free(anqp->hs20_operating_class);
    184 	wpabuf_free(anqp->hs20_osu_providers_list);
    185 #endif /* CONFIG_HS20 */
    186 
    187 	os_free(anqp);
    188 }
    189 
    190 
    191 static void wpa_bss_update_pending_connect(struct wpa_supplicant *wpa_s,
    192 					   struct wpa_bss *old_bss,
    193 					   struct wpa_bss *new_bss)
    194 {
    195 	struct wpa_radio_work *work;
    196 	struct wpa_connect_work *cwork;
    197 
    198 	work = radio_work_pending(wpa_s, "sme-connect");
    199 	if (!work)
    200 		work = radio_work_pending(wpa_s, "connect");
    201 	if (!work)
    202 		return;
    203 
    204 	cwork = work->ctx;
    205 	if (cwork->bss != old_bss)
    206 		return;
    207 
    208 	wpa_printf(MSG_DEBUG,
    209 		   "Update BSS pointer for the pending connect radio work");
    210 	cwork->bss = new_bss;
    211 	if (!new_bss)
    212 		cwork->bss_removed = 1;
    213 }
    214 
    215 
    216 static void wpa_bss_remove(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
    217 			   const char *reason)
    218 {
    219 	if (wpa_s->last_scan_res) {
    220 		unsigned int i;
    221 		for (i = 0; i < wpa_s->last_scan_res_used; i++) {
    222 			if (wpa_s->last_scan_res[i] == bss) {
    223 				os_memmove(&wpa_s->last_scan_res[i],
    224 					   &wpa_s->last_scan_res[i + 1],
    225 					   (wpa_s->last_scan_res_used - i - 1)
    226 					   * sizeof(struct wpa_bss *));
    227 				wpa_s->last_scan_res_used--;
    228 				break;
    229 			}
    230 		}
    231 	}
    232 	wpa_bss_update_pending_connect(wpa_s, bss, NULL);
    233 	dl_list_del(&bss->list);
    234 	dl_list_del(&bss->list_id);
    235 	wpa_s->num_bss--;
    236 	wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR
    237 		" SSID '%s' due to %s", bss->id, MAC2STR(bss->bssid),
    238 		wpa_ssid_txt(bss->ssid, bss->ssid_len), reason);
    239 	wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id);
    240 	wpa_bss_anqp_free(bss->anqp);
    241 	os_free(bss);
    242 }
    243 
    244 
    245 /**
    246  * wpa_bss_get - Fetch a BSS table entry based on BSSID and SSID
    247  * @wpa_s: Pointer to wpa_supplicant data
    248  * @bssid: BSSID
    249  * @ssid: SSID
    250  * @ssid_len: Length of @ssid
    251  * Returns: Pointer to the BSS entry or %NULL if not found
    252  */
    253 struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid,
    254 			     const u8 *ssid, size_t ssid_len)
    255 {
    256 	struct wpa_bss *bss;
    257 	if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
    258 		return NULL;
    259 	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
    260 		if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
    261 		    bss->ssid_len == ssid_len &&
    262 		    os_memcmp(bss->ssid, ssid, ssid_len) == 0)
    263 			return bss;
    264 	}
    265 	return NULL;
    266 }
    267 
    268 
    269 static void calculate_update_time(const struct os_reltime *fetch_time,
    270 				  unsigned int age_ms,
    271 				  struct os_reltime *update_time)
    272 {
    273 	os_time_t usec;
    274 
    275 	update_time->sec = fetch_time->sec;
    276 	update_time->usec = fetch_time->usec;
    277 	update_time->sec -= age_ms / 1000;
    278 	usec = (age_ms % 1000) * 1000;
    279 	if (update_time->usec < usec) {
    280 		update_time->sec--;
    281 		update_time->usec += 1000000;
    282 	}
    283 	update_time->usec -= usec;
    284 }
    285 
    286 
    287 static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src,
    288 			     struct os_reltime *fetch_time)
    289 {
    290 	dst->flags = src->flags;
    291 	os_memcpy(dst->bssid, src->bssid, ETH_ALEN);
    292 	dst->freq = src->freq;
    293 	dst->beacon_int = src->beacon_int;
    294 	dst->caps = src->caps;
    295 	dst->qual = src->qual;
    296 	dst->noise = src->noise;
    297 	dst->level = src->level;
    298 	dst->tsf = src->tsf;
    299 	dst->est_throughput = src->est_throughput;
    300 	dst->snr = src->snr;
    301 
    302 	calculate_update_time(fetch_time, src->age, &dst->last_update);
    303 }
    304 
    305 
    306 static int wpa_bss_known(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
    307 {
    308 	struct wpa_ssid *ssid;
    309 
    310 	for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
    311 		if (ssid->ssid == NULL || ssid->ssid_len == 0)
    312 			continue;
    313 		if (ssid->ssid_len == bss->ssid_len &&
    314 		    os_memcmp(ssid->ssid, bss->ssid, ssid->ssid_len) == 0)
    315 			return 1;
    316 	}
    317 
    318 	return 0;
    319 }
    320 
    321 
    322 static int wpa_bss_in_use(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
    323 {
    324 	if (bss == wpa_s->current_bss)
    325 		return 1;
    326 
    327 	if (wpa_s->current_bss &&
    328 	    (bss->ssid_len != wpa_s->current_bss->ssid_len ||
    329 	     os_memcmp(bss->ssid, wpa_s->current_bss->ssid,
    330 		       bss->ssid_len) != 0))
    331 		return 0; /* SSID has changed */
    332 
    333 	return !is_zero_ether_addr(bss->bssid) &&
    334 		(os_memcmp(bss->bssid, wpa_s->bssid, ETH_ALEN) == 0 ||
    335 		 os_memcmp(bss->bssid, wpa_s->pending_bssid, ETH_ALEN) == 0);
    336 }
    337 
    338 
    339 static int wpa_bss_remove_oldest_unknown(struct wpa_supplicant *wpa_s)
    340 {
    341 	struct wpa_bss *bss;
    342 
    343 	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
    344 		if (!wpa_bss_known(wpa_s, bss)) {
    345 			wpa_bss_remove(wpa_s, bss, __func__);
    346 			return 0;
    347 		}
    348 	}
    349 
    350 	return -1;
    351 }
    352 
    353 
    354 static int wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s)
    355 {
    356 	struct wpa_bss *bss;
    357 
    358 	/*
    359 	 * Remove the oldest entry that does not match with any configured
    360 	 * network.
    361 	 */
    362 	if (wpa_bss_remove_oldest_unknown(wpa_s) == 0)
    363 		return 0;
    364 
    365 	/*
    366 	 * Remove the oldest entry that isn't currently in use.
    367 	 */
    368 	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
    369 		if (!wpa_bss_in_use(wpa_s, bss)) {
    370 			wpa_bss_remove(wpa_s, bss, __func__);
    371 			return 0;
    372 		}
    373 	}
    374 
    375 	return -1;
    376 }
    377 
    378 
    379 static struct wpa_bss * wpa_bss_add(struct wpa_supplicant *wpa_s,
    380 				    const u8 *ssid, size_t ssid_len,
    381 				    struct wpa_scan_res *res,
    382 				    struct os_reltime *fetch_time)
    383 {
    384 	struct wpa_bss *bss;
    385 
    386 	bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len);
    387 	if (bss == NULL)
    388 		return NULL;
    389 	bss->id = wpa_s->bss_next_id++;
    390 	bss->last_update_idx = wpa_s->bss_update_idx;
    391 	wpa_bss_copy_res(bss, res, fetch_time);
    392 	os_memcpy(bss->ssid, ssid, ssid_len);
    393 	bss->ssid_len = ssid_len;
    394 	bss->ie_len = res->ie_len;
    395 	bss->beacon_ie_len = res->beacon_ie_len;
    396 	os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
    397 	wpa_bss_set_hessid(bss);
    398 
    399 	if (wpa_s->num_bss + 1 > wpa_s->conf->bss_max_count &&
    400 	    wpa_bss_remove_oldest(wpa_s) != 0) {
    401 		wpa_printf(MSG_ERROR, "Increasing the MAX BSS count to %d "
    402 			   "because all BSSes are in use. We should normally "
    403 			   "not get here!", (int) wpa_s->num_bss + 1);
    404 		wpa_s->conf->bss_max_count = wpa_s->num_bss + 1;
    405 	}
    406 
    407 	dl_list_add_tail(&wpa_s->bss, &bss->list);
    408 	dl_list_add_tail(&wpa_s->bss_id, &bss->list_id);
    409 	wpa_s->num_bss++;
    410 	wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR
    411 		" SSID '%s' freq %d",
    412 		bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len),
    413 		bss->freq);
    414 	wpas_notify_bss_added(wpa_s, bss->bssid, bss->id);
    415 	return bss;
    416 }
    417 
    418 
    419 static int are_ies_equal(const struct wpa_bss *old,
    420 			 const struct wpa_scan_res *new_res, u32 ie)
    421 {
    422 	const u8 *old_ie, *new_ie;
    423 	struct wpabuf *old_ie_buff = NULL;
    424 	struct wpabuf *new_ie_buff = NULL;
    425 	int new_ie_len, old_ie_len, ret, is_multi;
    426 
    427 	switch (ie) {
    428 	case WPA_IE_VENDOR_TYPE:
    429 		old_ie = wpa_bss_get_vendor_ie(old, ie);
    430 		new_ie = wpa_scan_get_vendor_ie(new_res, ie);
    431 		is_multi = 0;
    432 		break;
    433 	case WPS_IE_VENDOR_TYPE:
    434 		old_ie_buff = wpa_bss_get_vendor_ie_multi(old, ie);
    435 		new_ie_buff = wpa_scan_get_vendor_ie_multi(new_res, ie);
    436 		is_multi = 1;
    437 		break;
    438 	case WLAN_EID_RSN:
    439 	case WLAN_EID_SUPP_RATES:
    440 	case WLAN_EID_EXT_SUPP_RATES:
    441 		old_ie = wpa_bss_get_ie(old, ie);
    442 		new_ie = wpa_scan_get_ie(new_res, ie);
    443 		is_multi = 0;
    444 		break;
    445 	default:
    446 		wpa_printf(MSG_DEBUG, "bss: %s: cannot compare IEs", __func__);
    447 		return 0;
    448 	}
    449 
    450 	if (is_multi) {
    451 		/* in case of multiple IEs stored in buffer */
    452 		old_ie = old_ie_buff ? wpabuf_head_u8(old_ie_buff) : NULL;
    453 		new_ie = new_ie_buff ? wpabuf_head_u8(new_ie_buff) : NULL;
    454 		old_ie_len = old_ie_buff ? wpabuf_len(old_ie_buff) : 0;
    455 		new_ie_len = new_ie_buff ? wpabuf_len(new_ie_buff) : 0;
    456 	} else {
    457 		/* in case of single IE */
    458 		old_ie_len = old_ie ? old_ie[1] + 2 : 0;
    459 		new_ie_len = new_ie ? new_ie[1] + 2 : 0;
    460 	}
    461 
    462 	if (!old_ie || !new_ie)
    463 		ret = !old_ie && !new_ie;
    464 	else
    465 		ret = (old_ie_len == new_ie_len &&
    466 		       os_memcmp(old_ie, new_ie, old_ie_len) == 0);
    467 
    468 	wpabuf_free(old_ie_buff);
    469 	wpabuf_free(new_ie_buff);
    470 
    471 	return ret;
    472 }
    473 
    474 
    475 static u32 wpa_bss_compare_res(const struct wpa_bss *old,
    476 			       const struct wpa_scan_res *new_res)
    477 {
    478 	u32 changes = 0;
    479 	int caps_diff = old->caps ^ new_res->caps;
    480 
    481 	if (old->freq != new_res->freq)
    482 		changes |= WPA_BSS_FREQ_CHANGED_FLAG;
    483 
    484 	if (old->level != new_res->level)
    485 		changes |= WPA_BSS_SIGNAL_CHANGED_FLAG;
    486 
    487 	if (caps_diff & IEEE80211_CAP_PRIVACY)
    488 		changes |= WPA_BSS_PRIVACY_CHANGED_FLAG;
    489 
    490 	if (caps_diff & IEEE80211_CAP_IBSS)
    491 		changes |= WPA_BSS_MODE_CHANGED_FLAG;
    492 
    493 	if (old->ie_len == new_res->ie_len &&
    494 	    os_memcmp(old + 1, new_res + 1, old->ie_len) == 0)
    495 		return changes;
    496 	changes |= WPA_BSS_IES_CHANGED_FLAG;
    497 
    498 	if (!are_ies_equal(old, new_res, WPA_IE_VENDOR_TYPE))
    499 		changes |= WPA_BSS_WPAIE_CHANGED_FLAG;
    500 
    501 	if (!are_ies_equal(old, new_res, WLAN_EID_RSN))
    502 		changes |= WPA_BSS_RSNIE_CHANGED_FLAG;
    503 
    504 	if (!are_ies_equal(old, new_res, WPS_IE_VENDOR_TYPE))
    505 		changes |= WPA_BSS_WPS_CHANGED_FLAG;
    506 
    507 	if (!are_ies_equal(old, new_res, WLAN_EID_SUPP_RATES) ||
    508 	    !are_ies_equal(old, new_res, WLAN_EID_EXT_SUPP_RATES))
    509 		changes |= WPA_BSS_RATES_CHANGED_FLAG;
    510 
    511 	return changes;
    512 }
    513 
    514 
    515 static void notify_bss_changes(struct wpa_supplicant *wpa_s, u32 changes,
    516 			       const struct wpa_bss *bss)
    517 {
    518 	if (changes & WPA_BSS_FREQ_CHANGED_FLAG)
    519 		wpas_notify_bss_freq_changed(wpa_s, bss->id);
    520 
    521 	if (changes & WPA_BSS_SIGNAL_CHANGED_FLAG)
    522 		wpas_notify_bss_signal_changed(wpa_s, bss->id);
    523 
    524 	if (changes & WPA_BSS_PRIVACY_CHANGED_FLAG)
    525 		wpas_notify_bss_privacy_changed(wpa_s, bss->id);
    526 
    527 	if (changes & WPA_BSS_MODE_CHANGED_FLAG)
    528 		wpas_notify_bss_mode_changed(wpa_s, bss->id);
    529 
    530 	if (changes & WPA_BSS_WPAIE_CHANGED_FLAG)
    531 		wpas_notify_bss_wpaie_changed(wpa_s, bss->id);
    532 
    533 	if (changes & WPA_BSS_RSNIE_CHANGED_FLAG)
    534 		wpas_notify_bss_rsnie_changed(wpa_s, bss->id);
    535 
    536 	if (changes & WPA_BSS_WPS_CHANGED_FLAG)
    537 		wpas_notify_bss_wps_changed(wpa_s, bss->id);
    538 
    539 	if (changes & WPA_BSS_IES_CHANGED_FLAG)
    540 		wpas_notify_bss_ies_changed(wpa_s, bss->id);
    541 
    542 	if (changes & WPA_BSS_RATES_CHANGED_FLAG)
    543 		wpas_notify_bss_rates_changed(wpa_s, bss->id);
    544 
    545 	wpas_notify_bss_seen(wpa_s, bss->id);
    546 }
    547 
    548 
    549 static struct wpa_bss *
    550 wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
    551 	       struct wpa_scan_res *res, struct os_reltime *fetch_time)
    552 {
    553 	u32 changes;
    554 
    555 	changes = wpa_bss_compare_res(bss, res);
    556 	if (changes & WPA_BSS_FREQ_CHANGED_FLAG)
    557 		wpa_printf(MSG_DEBUG, "BSS: " MACSTR " changed freq %d --> %d",
    558 			   MAC2STR(bss->bssid), bss->freq, res->freq);
    559 	bss->scan_miss_count = 0;
    560 	bss->last_update_idx = wpa_s->bss_update_idx;
    561 	wpa_bss_copy_res(bss, res, fetch_time);
    562 	/* Move the entry to the end of the list */
    563 	dl_list_del(&bss->list);
    564 #ifdef CONFIG_P2P
    565 	if (wpa_bss_get_vendor_ie(bss, P2P_IE_VENDOR_TYPE) &&
    566 	    !wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE)) {
    567 		/*
    568 		 * This can happen when non-P2P station interface runs a scan
    569 		 * without P2P IE in the Probe Request frame. P2P GO would reply
    570 		 * to that with a Probe Response that does not include P2P IE.
    571 		 * Do not update the IEs in this BSS entry to avoid such loss of
    572 		 * information that may be needed for P2P operations to
    573 		 * determine group information.
    574 		 */
    575 		wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Do not update scan IEs for "
    576 			MACSTR " since that would remove P2P IE information",
    577 			MAC2STR(bss->bssid));
    578 	} else
    579 #endif /* CONFIG_P2P */
    580 	if (bss->ie_len + bss->beacon_ie_len >=
    581 	    res->ie_len + res->beacon_ie_len) {
    582 		os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
    583 		bss->ie_len = res->ie_len;
    584 		bss->beacon_ie_len = res->beacon_ie_len;
    585 	} else {
    586 		struct wpa_bss *nbss;
    587 		struct dl_list *prev = bss->list_id.prev;
    588 		dl_list_del(&bss->list_id);
    589 		nbss = os_realloc(bss, sizeof(*bss) + res->ie_len +
    590 				  res->beacon_ie_len);
    591 		if (nbss) {
    592 			unsigned int i;
    593 			for (i = 0; i < wpa_s->last_scan_res_used; i++) {
    594 				if (wpa_s->last_scan_res[i] == bss) {
    595 					wpa_s->last_scan_res[i] = nbss;
    596 					break;
    597 				}
    598 			}
    599 			if (wpa_s->current_bss == bss)
    600 				wpa_s->current_bss = nbss;
    601 			wpa_bss_update_pending_connect(wpa_s, bss, nbss);
    602 			bss = nbss;
    603 			os_memcpy(bss + 1, res + 1,
    604 				  res->ie_len + res->beacon_ie_len);
    605 			bss->ie_len = res->ie_len;
    606 			bss->beacon_ie_len = res->beacon_ie_len;
    607 		}
    608 		dl_list_add(prev, &bss->list_id);
    609 	}
    610 	if (changes & WPA_BSS_IES_CHANGED_FLAG)
    611 		wpa_bss_set_hessid(bss);
    612 	dl_list_add_tail(&wpa_s->bss, &bss->list);
    613 
    614 	notify_bss_changes(wpa_s, changes, bss);
    615 
    616 	return bss;
    617 }
    618 
    619 
    620 /**
    621  * wpa_bss_update_start - Start a BSS table update from scan results
    622  * @wpa_s: Pointer to wpa_supplicant data
    623  *
    624  * This function is called at the start of each BSS table update round for new
    625  * scan results. The actual scan result entries are indicated with calls to
    626  * wpa_bss_update_scan_res() and the update round is finished with a call to
    627  * wpa_bss_update_end().
    628  */
    629 void wpa_bss_update_start(struct wpa_supplicant *wpa_s)
    630 {
    631 	wpa_s->bss_update_idx++;
    632 	wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Start scan result update %u",
    633 		wpa_s->bss_update_idx);
    634 	wpa_s->last_scan_res_used = 0;
    635 }
    636 
    637 
    638 /**
    639  * wpa_bss_update_scan_res - Update a BSS table entry based on a scan result
    640  * @wpa_s: Pointer to wpa_supplicant data
    641  * @res: Scan result
    642  * @fetch_time: Time when the result was fetched from the driver
    643  *
    644  * This function updates a BSS table entry (or adds one) based on a scan result.
    645  * This is called separately for each scan result between the calls to
    646  * wpa_bss_update_start() and wpa_bss_update_end().
    647  */
    648 void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s,
    649 			     struct wpa_scan_res *res,
    650 			     struct os_reltime *fetch_time)
    651 {
    652 	const u8 *ssid, *p2p, *mesh;
    653 	struct wpa_bss *bss;
    654 
    655 	if (wpa_s->conf->ignore_old_scan_res) {
    656 		struct os_reltime update;
    657 		calculate_update_time(fetch_time, res->age, &update);
    658 		if (os_reltime_before(&update, &wpa_s->scan_trigger_time)) {
    659 			struct os_reltime age;
    660 			os_reltime_sub(&wpa_s->scan_trigger_time, &update,
    661 				       &age);
    662 			wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Ignore driver BSS "
    663 				"table entry that is %u.%06u seconds older "
    664 				"than our scan trigger",
    665 				(unsigned int) age.sec,
    666 				(unsigned int) age.usec);
    667 			return;
    668 		}
    669 	}
    670 
    671 	ssid = wpa_scan_get_ie(res, WLAN_EID_SSID);
    672 	if (ssid == NULL) {
    673 		wpa_dbg(wpa_s, MSG_DEBUG, "BSS: No SSID IE included for "
    674 			MACSTR, MAC2STR(res->bssid));
    675 		return;
    676 	}
    677 	if (ssid[1] > SSID_MAX_LEN) {
    678 		wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Too long SSID IE included for "
    679 			MACSTR, MAC2STR(res->bssid));
    680 		return;
    681 	}
    682 
    683 	p2p = wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE);
    684 #ifdef CONFIG_P2P
    685 	if (p2p == NULL &&
    686 	    wpa_s->p2p_group_interface != NOT_P2P_GROUP_INTERFACE) {
    687 		/*
    688 		 * If it's a P2P specific interface, then don't update
    689 		 * the scan result without a P2P IE.
    690 		 */
    691 		wpa_printf(MSG_DEBUG, "BSS: No P2P IE - skipping BSS " MACSTR
    692 			   " update for P2P interface", MAC2STR(res->bssid));
    693 		return;
    694 	}
    695 #endif /* CONFIG_P2P */
    696 	if (p2p && ssid[1] == P2P_WILDCARD_SSID_LEN &&
    697 	    os_memcmp(ssid + 2, P2P_WILDCARD_SSID, P2P_WILDCARD_SSID_LEN) == 0)
    698 		return; /* Skip P2P listen discovery results here */
    699 
    700 	/* TODO: add option for ignoring BSSes we are not interested in
    701 	 * (to save memory) */
    702 
    703 	mesh = wpa_scan_get_ie(res, WLAN_EID_MESH_ID);
    704 	if (mesh && mesh[1] <= SSID_MAX_LEN)
    705 		ssid = mesh;
    706 
    707 	bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]);
    708 	if (bss == NULL)
    709 		bss = wpa_bss_add(wpa_s, ssid + 2, ssid[1], res, fetch_time);
    710 	else {
    711 		bss = wpa_bss_update(wpa_s, bss, res, fetch_time);
    712 		if (wpa_s->last_scan_res) {
    713 			unsigned int i;
    714 			for (i = 0; i < wpa_s->last_scan_res_used; i++) {
    715 				if (bss == wpa_s->last_scan_res[i]) {
    716 					/* Already in the list */
    717 					return;
    718 				}
    719 			}
    720 		}
    721 	}
    722 
    723 	if (bss == NULL)
    724 		return;
    725 	if (wpa_s->last_scan_res_used >= wpa_s->last_scan_res_size) {
    726 		struct wpa_bss **n;
    727 		unsigned int siz;
    728 		if (wpa_s->last_scan_res_size == 0)
    729 			siz = 32;
    730 		else
    731 			siz = wpa_s->last_scan_res_size * 2;
    732 		n = os_realloc_array(wpa_s->last_scan_res, siz,
    733 				     sizeof(struct wpa_bss *));
    734 		if (n == NULL)
    735 			return;
    736 		wpa_s->last_scan_res = n;
    737 		wpa_s->last_scan_res_size = siz;
    738 	}
    739 
    740 	if (wpa_s->last_scan_res)
    741 		wpa_s->last_scan_res[wpa_s->last_scan_res_used++] = bss;
    742 }
    743 
    744 
    745 static int wpa_bss_included_in_scan(const struct wpa_bss *bss,
    746 				    const struct scan_info *info)
    747 {
    748 	int found;
    749 	size_t i;
    750 
    751 	if (info == NULL)
    752 		return 1;
    753 
    754 	if (info->num_freqs) {
    755 		found = 0;
    756 		for (i = 0; i < info->num_freqs; i++) {
    757 			if (bss->freq == info->freqs[i]) {
    758 				found = 1;
    759 				break;
    760 			}
    761 		}
    762 		if (!found)
    763 			return 0;
    764 	}
    765 
    766 	if (info->num_ssids) {
    767 		found = 0;
    768 		for (i = 0; i < info->num_ssids; i++) {
    769 			const struct wpa_driver_scan_ssid *s = &info->ssids[i];
    770 			if ((s->ssid == NULL || s->ssid_len == 0) ||
    771 			    (s->ssid_len == bss->ssid_len &&
    772 			     os_memcmp(s->ssid, bss->ssid, bss->ssid_len) ==
    773 			     0)) {
    774 				found = 1;
    775 				break;
    776 			}
    777 		}
    778 		if (!found)
    779 			return 0;
    780 	}
    781 
    782 	return 1;
    783 }
    784 
    785 
    786 /**
    787  * wpa_bss_update_end - End a BSS table update from scan results
    788  * @wpa_s: Pointer to wpa_supplicant data
    789  * @info: Information about scan parameters
    790  * @new_scan: Whether this update round was based on a new scan
    791  *
    792  * This function is called at the end of each BSS table update round for new
    793  * scan results. The start of the update was indicated with a call to
    794  * wpa_bss_update_start().
    795  */
    796 void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info,
    797 			int new_scan)
    798 {
    799 	struct wpa_bss *bss, *n;
    800 
    801 	os_get_reltime(&wpa_s->last_scan);
    802 	if ((info && info->aborted) || !new_scan)
    803 		return; /* do not expire entries without new scan */
    804 
    805 	dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
    806 		if (wpa_bss_in_use(wpa_s, bss))
    807 			continue;
    808 		if (!wpa_bss_included_in_scan(bss, info))
    809 			continue; /* expire only BSSes that were scanned */
    810 		if (bss->last_update_idx < wpa_s->bss_update_idx)
    811 			bss->scan_miss_count++;
    812 		if (bss->scan_miss_count >=
    813 		    wpa_s->conf->bss_expiration_scan_count) {
    814 			wpa_bss_remove(wpa_s, bss, "no match in scan");
    815 		}
    816 	}
    817 
    818 	wpa_printf(MSG_DEBUG, "BSS: last_scan_res_used=%u/%u",
    819 		   wpa_s->last_scan_res_used, wpa_s->last_scan_res_size);
    820 }
    821 
    822 
    823 /**
    824  * wpa_bss_flush_by_age - Flush old BSS entries
    825  * @wpa_s: Pointer to wpa_supplicant data
    826  * @age: Maximum entry age in seconds
    827  *
    828  * Remove BSS entries that have not been updated during the last @age seconds.
    829  */
    830 void wpa_bss_flush_by_age(struct wpa_supplicant *wpa_s, int age)
    831 {
    832 	struct wpa_bss *bss, *n;
    833 	struct os_reltime t;
    834 
    835 	if (dl_list_empty(&wpa_s->bss))
    836 		return;
    837 
    838 	os_get_reltime(&t);
    839 	t.sec -= age;
    840 
    841 	dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
    842 		if (wpa_bss_in_use(wpa_s, bss))
    843 			continue;
    844 
    845 		if (os_reltime_before(&bss->last_update, &t)) {
    846 			wpa_bss_remove(wpa_s, bss, __func__);
    847 		} else
    848 			break;
    849 	}
    850 }
    851 
    852 
    853 /**
    854  * wpa_bss_init - Initialize BSS table
    855  * @wpa_s: Pointer to wpa_supplicant data
    856  * Returns: 0 on success, -1 on failure
    857  *
    858  * This prepares BSS table lists and timer for periodic updates. The BSS table
    859  * is deinitialized with wpa_bss_deinit() once not needed anymore.
    860  */
    861 int wpa_bss_init(struct wpa_supplicant *wpa_s)
    862 {
    863 	dl_list_init(&wpa_s->bss);
    864 	dl_list_init(&wpa_s->bss_id);
    865 	return 0;
    866 }
    867 
    868 
    869 /**
    870  * wpa_bss_flush - Flush all unused BSS entries
    871  * @wpa_s: Pointer to wpa_supplicant data
    872  */
    873 void wpa_bss_flush(struct wpa_supplicant *wpa_s)
    874 {
    875 	struct wpa_bss *bss, *n;
    876 
    877 	wpa_s->clear_driver_scan_cache = 1;
    878 
    879 	if (wpa_s->bss.next == NULL)
    880 		return; /* BSS table not yet initialized */
    881 
    882 	dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
    883 		if (wpa_bss_in_use(wpa_s, bss))
    884 			continue;
    885 		wpa_bss_remove(wpa_s, bss, __func__);
    886 	}
    887 }
    888 
    889 
    890 /**
    891  * wpa_bss_deinit - Deinitialize BSS table
    892  * @wpa_s: Pointer to wpa_supplicant data
    893  */
    894 void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
    895 {
    896 	wpa_bss_flush(wpa_s);
    897 }
    898 
    899 
    900 /**
    901  * wpa_bss_get_bssid - Fetch a BSS table entry based on BSSID
    902  * @wpa_s: Pointer to wpa_supplicant data
    903  * @bssid: BSSID
    904  * Returns: Pointer to the BSS entry or %NULL if not found
    905  */
    906 struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
    907 				   const u8 *bssid)
    908 {
    909 	struct wpa_bss *bss;
    910 	if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
    911 		return NULL;
    912 	dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
    913 		if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
    914 			return bss;
    915 	}
    916 	return NULL;
    917 }
    918 
    919 
    920 /**
    921  * wpa_bss_get_bssid_latest - Fetch the latest BSS table entry based on BSSID
    922  * @wpa_s: Pointer to wpa_supplicant data
    923  * @bssid: BSSID
    924  * Returns: Pointer to the BSS entry or %NULL if not found
    925  *
    926  * This function is like wpa_bss_get_bssid(), but full BSS table is iterated to
    927  * find the entry that has the most recent update. This can help in finding the
    928  * correct entry in cases where the SSID of the AP may have changed recently
    929  * (e.g., in WPS reconfiguration cases).
    930  */
    931 struct wpa_bss * wpa_bss_get_bssid_latest(struct wpa_supplicant *wpa_s,
    932 					  const u8 *bssid)
    933 {
    934 	struct wpa_bss *bss, *found = NULL;
    935 	if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
    936 		return NULL;
    937 	dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
    938 		if (os_memcmp(bss->bssid, bssid, ETH_ALEN) != 0)
    939 			continue;
    940 		if (found == NULL ||
    941 		    os_reltime_before(&found->last_update, &bss->last_update))
    942 			found = bss;
    943 	}
    944 	return found;
    945 }
    946 
    947 
    948 #ifdef CONFIG_P2P
    949 /**
    950  * wpa_bss_get_p2p_dev_addr - Fetch a BSS table entry based on P2P Device Addr
    951  * @wpa_s: Pointer to wpa_supplicant data
    952  * @dev_addr: P2P Device Address of the GO
    953  * Returns: Pointer to the BSS entry or %NULL if not found
    954  */
    955 struct wpa_bss * wpa_bss_get_p2p_dev_addr(struct wpa_supplicant *wpa_s,
    956 					  const u8 *dev_addr)
    957 {
    958 	struct wpa_bss *bss;
    959 	dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
    960 		u8 addr[ETH_ALEN];
    961 		if (p2p_parse_dev_addr((const u8 *) (bss + 1), bss->ie_len,
    962 				       addr) == 0 &&
    963 		    os_memcmp(addr, dev_addr, ETH_ALEN) == 0)
    964 			return bss;
    965 	}
    966 	return NULL;
    967 }
    968 #endif /* CONFIG_P2P */
    969 
    970 
    971 /**
    972  * wpa_bss_get_id - Fetch a BSS table entry based on identifier
    973  * @wpa_s: Pointer to wpa_supplicant data
    974  * @id: Unique identifier (struct wpa_bss::id) assigned for the entry
    975  * Returns: Pointer to the BSS entry or %NULL if not found
    976  */
    977 struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id)
    978 {
    979 	struct wpa_bss *bss;
    980 	dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
    981 		if (bss->id == id)
    982 			return bss;
    983 	}
    984 	return NULL;
    985 }
    986 
    987 
    988 /**
    989  * wpa_bss_get_id_range - Fetch a BSS table entry based on identifier range
    990  * @wpa_s: Pointer to wpa_supplicant data
    991  * @idf: Smallest allowed identifier assigned for the entry
    992  * @idf: Largest allowed identifier assigned for the entry
    993  * Returns: Pointer to the BSS entry or %NULL if not found
    994  *
    995  * This function is similar to wpa_bss_get_id() but allows a BSS entry with the
    996  * smallest id value to be fetched within the specified range without the
    997  * caller having to know the exact id.
    998  */
    999 struct wpa_bss * wpa_bss_get_id_range(struct wpa_supplicant *wpa_s,
   1000 				      unsigned int idf, unsigned int idl)
   1001 {
   1002 	struct wpa_bss *bss;
   1003 	dl_list_for_each(bss, &wpa_s->bss_id, struct wpa_bss, list_id) {
   1004 		if (bss->id >= idf && bss->id <= idl)
   1005 			return bss;
   1006 	}
   1007 	return NULL;
   1008 }
   1009 
   1010 
   1011 /**
   1012  * wpa_bss_get_ie - Fetch a specified information element from a BSS entry
   1013  * @bss: BSS table entry
   1014  * @ie: Information element identitifier (WLAN_EID_*)
   1015  * Returns: Pointer to the information element (id field) or %NULL if not found
   1016  *
   1017  * This function returns the first matching information element in the BSS
   1018  * entry.
   1019  */
   1020 const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie)
   1021 {
   1022 	return get_ie((const u8 *) (bss + 1), bss->ie_len, ie);
   1023 }
   1024 
   1025 
   1026 /**
   1027  * wpa_bss_get_vendor_ie - Fetch a vendor information element from a BSS entry
   1028  * @bss: BSS table entry
   1029  * @vendor_type: Vendor type (four octets starting the IE payload)
   1030  * Returns: Pointer to the information element (id field) or %NULL if not found
   1031  *
   1032  * This function returns the first matching information element in the BSS
   1033  * entry.
   1034  */
   1035 const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type)
   1036 {
   1037 	const u8 *end, *pos;
   1038 
   1039 	pos = (const u8 *) (bss + 1);
   1040 	end = pos + bss->ie_len;
   1041 
   1042 	while (end - pos > 1) {
   1043 		if (2 + pos[1] > end - pos)
   1044 			break;
   1045 		if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
   1046 		    vendor_type == WPA_GET_BE32(&pos[2]))
   1047 			return pos;
   1048 		pos += 2 + pos[1];
   1049 	}
   1050 
   1051 	return NULL;
   1052 }
   1053 
   1054 
   1055 /**
   1056  * wpa_bss_get_vendor_ie_beacon - Fetch a vendor information from a BSS entry
   1057  * @bss: BSS table entry
   1058  * @vendor_type: Vendor type (four octets starting the IE payload)
   1059  * Returns: Pointer to the information element (id field) or %NULL if not found
   1060  *
   1061  * This function returns the first matching information element in the BSS
   1062  * entry.
   1063  *
   1064  * This function is like wpa_bss_get_vendor_ie(), but uses IE buffer only
   1065  * from Beacon frames instead of either Beacon or Probe Response frames.
   1066  */
   1067 const u8 * wpa_bss_get_vendor_ie_beacon(const struct wpa_bss *bss,
   1068 					u32 vendor_type)
   1069 {
   1070 	const u8 *end, *pos;
   1071 
   1072 	if (bss->beacon_ie_len == 0)
   1073 		return NULL;
   1074 
   1075 	pos = (const u8 *) (bss + 1);
   1076 	pos += bss->ie_len;
   1077 	end = pos + bss->beacon_ie_len;
   1078 
   1079 	while (end - pos > 1) {
   1080 		if (2 + pos[1] > end - pos)
   1081 			break;
   1082 		if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
   1083 		    vendor_type == WPA_GET_BE32(&pos[2]))
   1084 			return pos;
   1085 		pos += 2 + pos[1];
   1086 	}
   1087 
   1088 	return NULL;
   1089 }
   1090 
   1091 
   1092 /**
   1093  * wpa_bss_get_vendor_ie_multi - Fetch vendor IE data from a BSS entry
   1094  * @bss: BSS table entry
   1095  * @vendor_type: Vendor type (four octets starting the IE payload)
   1096  * Returns: Pointer to the information element payload or %NULL if not found
   1097  *
   1098  * This function returns concatenated payload of possibly fragmented vendor
   1099  * specific information elements in the BSS entry. The caller is responsible for
   1100  * freeing the returned buffer.
   1101  */
   1102 struct wpabuf * wpa_bss_get_vendor_ie_multi(const struct wpa_bss *bss,
   1103 					    u32 vendor_type)
   1104 {
   1105 	struct wpabuf *buf;
   1106 	const u8 *end, *pos;
   1107 
   1108 	buf = wpabuf_alloc(bss->ie_len);
   1109 	if (buf == NULL)
   1110 		return NULL;
   1111 
   1112 	pos = (const u8 *) (bss + 1);
   1113 	end = pos + bss->ie_len;
   1114 
   1115 	while (end - pos > 1) {
   1116 		if (2 + pos[1] > end - pos)
   1117 			break;
   1118 		if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
   1119 		    vendor_type == WPA_GET_BE32(&pos[2]))
   1120 			wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
   1121 		pos += 2 + pos[1];
   1122 	}
   1123 
   1124 	if (wpabuf_len(buf) == 0) {
   1125 		wpabuf_free(buf);
   1126 		buf = NULL;
   1127 	}
   1128 
   1129 	return buf;
   1130 }
   1131 
   1132 
   1133 /**
   1134  * wpa_bss_get_vendor_ie_multi_beacon - Fetch vendor IE data from a BSS entry
   1135  * @bss: BSS table entry
   1136  * @vendor_type: Vendor type (four octets starting the IE payload)
   1137  * Returns: Pointer to the information element payload or %NULL if not found
   1138  *
   1139  * This function returns concatenated payload of possibly fragmented vendor
   1140  * specific information elements in the BSS entry. The caller is responsible for
   1141  * freeing the returned buffer.
   1142  *
   1143  * This function is like wpa_bss_get_vendor_ie_multi(), but uses IE buffer only
   1144  * from Beacon frames instead of either Beacon or Probe Response frames.
   1145  */
   1146 struct wpabuf * wpa_bss_get_vendor_ie_multi_beacon(const struct wpa_bss *bss,
   1147 						   u32 vendor_type)
   1148 {
   1149 	struct wpabuf *buf;
   1150 	const u8 *end, *pos;
   1151 
   1152 	buf = wpabuf_alloc(bss->beacon_ie_len);
   1153 	if (buf == NULL)
   1154 		return NULL;
   1155 
   1156 	pos = (const u8 *) (bss + 1);
   1157 	pos += bss->ie_len;
   1158 	end = pos + bss->beacon_ie_len;
   1159 
   1160 	while (end - pos > 1) {
   1161 		if (2 + pos[1] > end - pos)
   1162 			break;
   1163 		if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
   1164 		    vendor_type == WPA_GET_BE32(&pos[2]))
   1165 			wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
   1166 		pos += 2 + pos[1];
   1167 	}
   1168 
   1169 	if (wpabuf_len(buf) == 0) {
   1170 		wpabuf_free(buf);
   1171 		buf = NULL;
   1172 	}
   1173 
   1174 	return buf;
   1175 }
   1176 
   1177 
   1178 /**
   1179  * wpa_bss_get_max_rate - Get maximum legacy TX rate supported in a BSS
   1180  * @bss: BSS table entry
   1181  * Returns: Maximum legacy rate in units of 500 kbps
   1182  */
   1183 int wpa_bss_get_max_rate(const struct wpa_bss *bss)
   1184 {
   1185 	int rate = 0;
   1186 	const u8 *ie;
   1187 	int i;
   1188 
   1189 	ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
   1190 	for (i = 0; ie && i < ie[1]; i++) {
   1191 		if ((ie[i + 2] & 0x7f) > rate)
   1192 			rate = ie[i + 2] & 0x7f;
   1193 	}
   1194 
   1195 	ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
   1196 	for (i = 0; ie && i < ie[1]; i++) {
   1197 		if ((ie[i + 2] & 0x7f) > rate)
   1198 			rate = ie[i + 2] & 0x7f;
   1199 	}
   1200 
   1201 	return rate;
   1202 }
   1203 
   1204 
   1205 /**
   1206  * wpa_bss_get_bit_rates - Get legacy TX rates supported in a BSS
   1207  * @bss: BSS table entry
   1208  * @rates: Buffer for returning a pointer to the rates list (units of 500 kbps)
   1209  * Returns: number of legacy TX rates or -1 on failure
   1210  *
   1211  * The caller is responsible for freeing the returned buffer with os_free() in
   1212  * case of success.
   1213  */
   1214 int wpa_bss_get_bit_rates(const struct wpa_bss *bss, u8 **rates)
   1215 {
   1216 	const u8 *ie, *ie2;
   1217 	int i, j;
   1218 	unsigned int len;
   1219 	u8 *r;
   1220 
   1221 	ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
   1222 	ie2 = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
   1223 
   1224 	len = (ie ? ie[1] : 0) + (ie2 ? ie2[1] : 0);
   1225 
   1226 	r = os_malloc(len);
   1227 	if (!r)
   1228 		return -1;
   1229 
   1230 	for (i = 0; ie && i < ie[1]; i++)
   1231 		r[i] = ie[i + 2] & 0x7f;
   1232 
   1233 	for (j = 0; ie2 && j < ie2[1]; j++)
   1234 		r[i + j] = ie2[j + 2] & 0x7f;
   1235 
   1236 	*rates = r;
   1237 	return len;
   1238 }
   1239