/*
* BSS table
* Copyright (c) 2009-2012, Jouni Malinen <j@w1.fi>
*
* This software may be distributed under the terms of the BSD license.
* See README 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 "config.h"
#include "notify.h"
#include "scan.h"
#include "bss.h"
/**
* WPA_BSS_EXPIRATION_PERIOD - Period of expiration run in seconds
*/
#define WPA_BSS_EXPIRATION_PERIOD 10
#define WPA_BSS_FREQ_CHANGED_FLAG BIT(0)
#define WPA_BSS_SIGNAL_CHANGED_FLAG BIT(1)
#define WPA_BSS_PRIVACY_CHANGED_FLAG BIT(2)
#define WPA_BSS_MODE_CHANGED_FLAG BIT(3)
#define WPA_BSS_WPAIE_CHANGED_FLAG BIT(4)
#define WPA_BSS_RSNIE_CHANGED_FLAG BIT(5)
#define WPA_BSS_WPS_CHANGED_FLAG BIT(6)
#define WPA_BSS_RATES_CHANGED_FLAG BIT(7)
#define WPA_BSS_IES_CHANGED_FLAG BIT(8)
static void wpa_bss_set_hessid(struct wpa_bss *bss)
{
#ifdef CONFIG_INTERWORKING
const u8 *ie = wpa_bss_get_ie(bss, WLAN_EID_INTERWORKING);
if (ie == NULL || (ie[1] != 7 && ie[1] != 9)) {
os_memset(bss->hessid, 0, ETH_ALEN);
return;
}
if (ie[1] == 7)
os_memcpy(bss->hessid, ie + 3, ETH_ALEN);
else
os_memcpy(bss->hessid, ie + 5, ETH_ALEN);
#endif /* CONFIG_INTERWORKING */
}
/**
* wpa_bss_anqp_alloc - Allocate ANQP data structure for a BSS entry
* Returns: Allocated ANQP data structure or %NULL on failure
*
* The allocated ANQP data structure has its users count set to 1. It may be
* shared by multiple BSS entries and each shared entry is freed with
* wpa_bss_anqp_free().
*/
struct wpa_bss_anqp * wpa_bss_anqp_alloc(void)
{
struct wpa_bss_anqp *anqp;
anqp = os_zalloc(sizeof(*anqp));
if (anqp == NULL)
return NULL;
anqp->users = 1;
return anqp;
}
/**
* wpa_bss_anqp_clone - Clone an ANQP data structure
* @anqp: ANQP data structure from wpa_bss_anqp_alloc()
* Returns: Cloned ANQP data structure or %NULL on failure
*/
static struct wpa_bss_anqp * wpa_bss_anqp_clone(struct wpa_bss_anqp *anqp)
{
struct wpa_bss_anqp *n;
n = os_zalloc(sizeof(*n));
if (n == NULL)
return NULL;
#define ANQP_DUP(f) if (anqp->f) n->f = wpabuf_dup(anqp->f)
#ifdef CONFIG_INTERWORKING
ANQP_DUP(venue_name);
ANQP_DUP(network_auth_type);
ANQP_DUP(roaming_consortium);
ANQP_DUP(ip_addr_type_availability);
ANQP_DUP(nai_realm);
ANQP_DUP(anqp_3gpp);
ANQP_DUP(domain_name);
#endif /* CONFIG_INTERWORKING */
#ifdef CONFIG_HS20
ANQP_DUP(hs20_operator_friendly_name);
ANQP_DUP(hs20_wan_metrics);
ANQP_DUP(hs20_connection_capability);
ANQP_DUP(hs20_operating_class);
ANQP_DUP(hs20_osu_providers_list);
#endif /* CONFIG_HS20 */
#undef ANQP_DUP
return n;
}
/**
* wpa_bss_anqp_unshare_alloc - Unshare ANQP data (if shared) in a BSS entry
* @bss: BSS entry
* Returns: 0 on success, -1 on failure
*
* This function ensures the specific BSS entry has an ANQP data structure that
* is not shared with any other BSS entry.
*/
int wpa_bss_anqp_unshare_alloc(struct wpa_bss *bss)
{
struct wpa_bss_anqp *anqp;
if (bss->anqp && bss->anqp->users > 1) {
/* allocated, but shared - clone an unshared copy */
anqp = wpa_bss_anqp_clone(bss->anqp);
if (anqp == NULL)
return -1;
anqp->users = 1;
bss->anqp->users--;
bss->anqp = anqp;
return 0;
}
if (bss->anqp)
return 0; /* already allocated and not shared */
/* not allocated - allocate a new storage area */
bss->anqp = wpa_bss_anqp_alloc();
return bss->anqp ? 0 : -1;
}
/**
* wpa_bss_anqp_free - Free an ANQP data structure
* @anqp: ANQP data structure from wpa_bss_anqp_alloc() or wpa_bss_anqp_clone()
*/
static void wpa_bss_anqp_free(struct wpa_bss_anqp *anqp)
{
if (anqp == NULL)
return;
anqp->users--;
if (anqp->users > 0) {
/* Another BSS entry holds a pointer to this ANQP info */
return;
}
#ifdef CONFIG_INTERWORKING
wpabuf_free(anqp->venue_name);
wpabuf_free(anqp->network_auth_type);
wpabuf_free(anqp->roaming_consortium);
wpabuf_free(anqp->ip_addr_type_availability);
wpabuf_free(anqp->nai_realm);
wpabuf_free(anqp->anqp_3gpp);
wpabuf_free(anqp->domain_name);
#endif /* CONFIG_INTERWORKING */
#ifdef CONFIG_HS20
wpabuf_free(anqp->hs20_operator_friendly_name);
wpabuf_free(anqp->hs20_wan_metrics);
wpabuf_free(anqp->hs20_connection_capability);
wpabuf_free(anqp->hs20_operating_class);
wpabuf_free(anqp->hs20_osu_providers_list);
#endif /* CONFIG_HS20 */
os_free(anqp);
}
static void wpa_bss_remove(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
const char *reason)
{
if (wpa_s->last_scan_res) {
unsigned int i;
for (i = 0; i < wpa_s->last_scan_res_used; i++) {
if (wpa_s->last_scan_res[i] == bss) {
os_memmove(&wpa_s->last_scan_res[i],
&wpa_s->last_scan_res[i + 1],
(wpa_s->last_scan_res_used - i - 1)
* sizeof(struct wpa_bss *));
wpa_s->last_scan_res_used--;
break;
}
}
}
dl_list_del(&bss->list);
dl_list_del(&bss->list_id);
wpa_s->num_bss--;
wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR
" SSID '%s' due to %s", bss->id, MAC2STR(bss->bssid),
wpa_ssid_txt(bss->ssid, bss->ssid_len), reason);
wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id);
wpa_bss_anqp_free(bss->anqp);
os_free(bss);
}
/**
* wpa_bss_get - Fetch a BSS table entry based on BSSID and SSID
* @wpa_s: Pointer to wpa_supplicant data
* @bssid: BSSID
* @ssid: SSID
* @ssid_len: Length of @ssid
* Returns: Pointer to the BSS entry or %NULL if not found
*/
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;
if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
return NULL;
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 calculate_update_time(const struct os_reltime *fetch_time,
unsigned int age_ms,
struct os_reltime *update_time)
{
os_time_t usec;
update_time->sec = fetch_time->sec;
update_time->usec = fetch_time->usec;
update_time->sec -= age_ms / 1000;
usec = (age_ms % 1000) * 1000;
if (update_time->usec < usec) {
update_time->sec--;
update_time->usec += 1000000;
}
update_time->usec -= usec;
}
static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src,
struct os_reltime *fetch_time)
{
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;
calculate_update_time(fetch_time, src->age, &dst->last_update);
}
static int wpa_bss_known(struct wpa_supplicant *wpa_s, struct wpa_bss *bss)
{
struct wpa_ssid *ssid;
for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
if (ssid->ssid == NULL || ssid->ssid_len == 0)
continue;
if (ssid->ssid_len == bss->ssid_len &&
os_memcmp(ssid->ssid, bss->ssid, ssid->ssid_len) == 0)
return 1;
}
return 0;
}
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;
}
static int wpa_bss_remove_oldest_unknown(struct wpa_supplicant *wpa_s)
{
struct wpa_bss *bss;
dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
if (!wpa_bss_known(wpa_s, bss)) {
wpa_bss_remove(wpa_s, bss, __func__);
return 0;
}
}
return -1;
}
static int wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s)
{
struct wpa_bss *bss;
/*
* Remove the oldest entry that does not match with any configured
* network.
*/
if (wpa_bss_remove_oldest_unknown(wpa_s) == 0)
return 0;
/*
* Remove the oldest entry that isn't currently in use.
*/
dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
if (!wpa_bss_in_use(wpa_s, bss)) {
wpa_bss_remove(wpa_s, bss, __func__);
return 0;
}
}
return -1;
}
static struct wpa_bss * wpa_bss_add(struct wpa_supplicant *wpa_s,
const u8 *ssid, size_t ssid_len,
struct wpa_scan_res *res,
struct os_reltime *fetch_time)
{
struct wpa_bss *bss;
bss = os_zalloc(sizeof(*bss) + res->ie_len + res->beacon_ie_len);
if (bss == NULL)
return NULL;
bss->id = wpa_s->bss_next_id++;
bss->last_update_idx = wpa_s->bss_update_idx;
wpa_bss_copy_res(bss, res, fetch_time);
os_memcpy(bss->ssid, ssid, ssid_len);
bss->ssid_len = ssid_len;
bss->ie_len = res->ie_len;
bss->beacon_ie_len = res->beacon_ie_len;
os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
wpa_bss_set_hessid(bss);
if (wpa_s->num_bss + 1 > wpa_s->conf->bss_max_count &&
wpa_bss_remove_oldest(wpa_s) != 0) {
wpa_printf(MSG_ERROR, "Increasing the MAX BSS count to %d "
"because all BSSes are in use. We should normally "
"not get here!", (int) wpa_s->num_bss + 1);
wpa_s->conf->bss_max_count = wpa_s->num_bss + 1;
}
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_dbg(wpa_s, 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);
return bss;
}
static int are_ies_equal(const struct wpa_bss *old,
const struct wpa_scan_res *new, u32 ie)
{
const u8 *old_ie, *new_ie;
struct wpabuf *old_ie_buff = NULL;
struct wpabuf *new_ie_buff = NULL;
int new_ie_len, old_ie_len, ret, is_multi;
switch (ie) {
case WPA_IE_VENDOR_TYPE:
old_ie = wpa_bss_get_vendor_ie(old, ie);
new_ie = wpa_scan_get_vendor_ie(new, ie);
is_multi = 0;
break;
case WPS_IE_VENDOR_TYPE:
old_ie_buff = wpa_bss_get_vendor_ie_multi(old, ie);
new_ie_buff = wpa_scan_get_vendor_ie_multi(new, ie);
is_multi = 1;
break;
case WLAN_EID_RSN:
case WLAN_EID_SUPP_RATES:
case WLAN_EID_EXT_SUPP_RATES:
old_ie = wpa_bss_get_ie(old, ie);
new_ie = wpa_scan_get_ie(new, ie);
is_multi = 0;
break;
default:
wpa_printf(MSG_DEBUG, "bss: %s: cannot compare IEs", __func__);
return 0;
}
if (is_multi) {
/* in case of multiple IEs stored in buffer */
old_ie = old_ie_buff ? wpabuf_head_u8(old_ie_buff) : NULL;
new_ie = new_ie_buff ? wpabuf_head_u8(new_ie_buff) : NULL;
old_ie_len = old_ie_buff ? wpabuf_len(old_ie_buff) : 0;
new_ie_len = new_ie_buff ? wpabuf_len(new_ie_buff) : 0;
} else {
/* in case of single IE */
old_ie_len = old_ie ? old_ie[1] + 2 : 0;
new_ie_len = new_ie ? new_ie[1] + 2 : 0;
}
if (!old_ie || !new_ie)
ret = !old_ie && !new_ie;
else
ret = (old_ie_len == new_ie_len &&
os_memcmp(old_ie, new_ie, old_ie_len) == 0);
wpabuf_free(old_ie_buff);
wpabuf_free(new_ie_buff);
return ret;
}
static u32 wpa_bss_compare_res(const struct wpa_bss *old,
const struct wpa_scan_res *new)
{
u32 changes = 0;
int caps_diff = old->caps ^ new->caps;
if (old->freq != new->freq)
changes |= WPA_BSS_FREQ_CHANGED_FLAG;
if (old->level != new->level)
changes |= WPA_BSS_SIGNAL_CHANGED_FLAG;
if (caps_diff & IEEE80211_CAP_PRIVACY)
changes |= WPA_BSS_PRIVACY_CHANGED_FLAG;
if (caps_diff & IEEE80211_CAP_IBSS)
changes |= WPA_BSS_MODE_CHANGED_FLAG;
if (old->ie_len == new->ie_len &&
os_memcmp(old + 1, new + 1, old->ie_len) == 0)
return changes;
changes |= WPA_BSS_IES_CHANGED_FLAG;
if (!are_ies_equal(old, new, WPA_IE_VENDOR_TYPE))
changes |= WPA_BSS_WPAIE_CHANGED_FLAG;
if (!are_ies_equal(old, new, WLAN_EID_RSN))
changes |= WPA_BSS_RSNIE_CHANGED_FLAG;
if (!are_ies_equal(old, new, WPS_IE_VENDOR_TYPE))
changes |= WPA_BSS_WPS_CHANGED_FLAG;
if (!are_ies_equal(old, new, WLAN_EID_SUPP_RATES) ||
!are_ies_equal(old, new, WLAN_EID_EXT_SUPP_RATES))
changes |= WPA_BSS_RATES_CHANGED_FLAG;
return changes;
}
static void notify_bss_changes(struct wpa_supplicant *wpa_s, u32 changes,
const struct wpa_bss *bss)
{
if (changes & WPA_BSS_FREQ_CHANGED_FLAG)
wpas_notify_bss_freq_changed(wpa_s, bss->id);
if (changes & WPA_BSS_SIGNAL_CHANGED_FLAG)
wpas_notify_bss_signal_changed(wpa_s, bss->id);
if (changes & WPA_BSS_PRIVACY_CHANGED_FLAG)
wpas_notify_bss_privacy_changed(wpa_s, bss->id);
if (changes & WPA_BSS_MODE_CHANGED_FLAG)
wpas_notify_bss_mode_changed(wpa_s, bss->id);
if (changes & WPA_BSS_WPAIE_CHANGED_FLAG)
wpas_notify_bss_wpaie_changed(wpa_s, bss->id);
if (changes & WPA_BSS_RSNIE_CHANGED_FLAG)
wpas_notify_bss_rsnie_changed(wpa_s, bss->id);
if (changes & WPA_BSS_WPS_CHANGED_FLAG)
wpas_notify_bss_wps_changed(wpa_s, bss->id);
if (changes & WPA_BSS_IES_CHANGED_FLAG)
wpas_notify_bss_ies_changed(wpa_s, bss->id);
if (changes & WPA_BSS_RATES_CHANGED_FLAG)
wpas_notify_bss_rates_changed(wpa_s, bss->id);
}
static struct wpa_bss *
wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
struct wpa_scan_res *res, struct os_reltime *fetch_time)
{
u32 changes;
changes = wpa_bss_compare_res(bss, res);
bss->scan_miss_count = 0;
bss->last_update_idx = wpa_s->bss_update_idx;
wpa_bss_copy_res(bss, res, fetch_time);
/* Move the entry to the end of the list */
dl_list_del(&bss->list);
#ifdef CONFIG_P2P
if (wpa_bss_get_vendor_ie(bss, P2P_IE_VENDOR_TYPE) &&
!wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE)) {
/*
* This can happen when non-P2P station interface runs a scan
* without P2P IE in the Probe Request frame. P2P GO would reply
* to that with a Probe Response that does not include P2P IE.
* Do not update the IEs in this BSS entry to avoid such loss of
* information that may be needed for P2P operations to
* determine group information.
*/
wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Do not update scan IEs for "
MACSTR " since that would remove P2P IE information",
MAC2STR(bss->bssid));
} else
#endif /* CONFIG_P2P */
if (bss->ie_len + bss->beacon_ie_len >=
res->ie_len + res->beacon_ie_len) {
os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_ie_len);
bss->ie_len = res->ie_len;
bss->beacon_ie_len = res->beacon_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 +
res->beacon_ie_len);
if (nbss) {
unsigned int i;
for (i = 0; i < wpa_s->last_scan_res_used; i++) {
if (wpa_s->last_scan_res[i] == bss) {
wpa_s->last_scan_res[i] = nbss;
break;
}
}
if (wpa_s->current_bss == bss)
wpa_s->current_bss = nbss;
bss = nbss;
os_memcpy(bss + 1, res + 1,
res->ie_len + res->beacon_ie_len);
bss->ie_len = res->ie_len;
bss->beacon_ie_len = res->beacon_ie_len;
}
dl_list_add(prev, &bss->list_id);
}
if (changes & WPA_BSS_IES_CHANGED_FLAG)
wpa_bss_set_hessid(bss);
dl_list_add_tail(&wpa_s->bss, &bss->list);
notify_bss_changes(wpa_s, changes, bss);
return bss;
}
/**
* wpa_bss_update_start - Start a BSS table update from scan results
* @wpa_s: Pointer to wpa_supplicant data
*
* This function is called at the start of each BSS table update round for new
* scan results. The actual scan result entries are indicated with calls to
* wpa_bss_update_scan_res() and the update round is finished with a call to
* wpa_bss_update_end().
*/
void wpa_bss_update_start(struct wpa_supplicant *wpa_s)
{
wpa_s->bss_update_idx++;
wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Start scan result update %u",
wpa_s->bss_update_idx);
wpa_s->last_scan_res_used = 0;
}
/**
* wpa_bss_update_scan_res - Update a BSS table entry based on a scan result
* @wpa_s: Pointer to wpa_supplicant data
* @res: Scan result
* @fetch_time: Time when the result was fetched from the driver
*
* This function updates a BSS table entry (or adds one) based on a scan result.
* This is called separately for each scan result between the calls to
* wpa_bss_update_start() and wpa_bss_update_end().
*/
void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s,
struct wpa_scan_res *res,
struct os_reltime *fetch_time)
{
const u8 *ssid, *p2p;
struct wpa_bss *bss;
if (wpa_s->conf->ignore_old_scan_res) {
struct os_reltime update;
calculate_update_time(fetch_time, res->age, &update);
if (os_reltime_before(&update, &wpa_s->scan_trigger_time)) {
struct os_reltime age;
os_reltime_sub(&wpa_s->scan_trigger_time, &update,
&age);
wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Ignore driver BSS "
"table entry that is %u.%06u seconds older "
"than our scan trigger",
(unsigned int) age.sec,
(unsigned int) age.usec);
return;
}
}
ssid = wpa_scan_get_ie(res, WLAN_EID_SSID);
if (ssid == NULL) {
wpa_dbg(wpa_s, MSG_DEBUG, "BSS: No SSID IE included for "
MACSTR, MAC2STR(res->bssid));
return;
}
if (ssid[1] > 32) {
wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Too long SSID IE included for "
MACSTR, MAC2STR(res->bssid));
return;
}
p2p = wpa_scan_get_vendor_ie(res, P2P_IE_VENDOR_TYPE);
#ifdef CONFIG_P2P
if (p2p == NULL &&
wpa_s->p2p_group_interface != NOT_P2P_GROUP_INTERFACE) {
/*
* If it's a P2P specific interface, then don't update
* the scan result without a P2P IE.
*/
wpa_printf(MSG_DEBUG, "BSS: No P2P IE - skipping BSS " MACSTR
" update for P2P interface", MAC2STR(res->bssid));
return;
}
#endif /* CONFIG_P2P */
if (p2p && ssid[1] == P2P_WILDCARD_SSID_LEN &&
os_memcmp(ssid + 2, P2P_WILDCARD_SSID, P2P_WILDCARD_SSID_LEN) == 0)
return; /* Skip P2P listen discovery results here */
/* 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)
bss = wpa_bss_add(wpa_s, ssid + 2, ssid[1], res, fetch_time);
else {
bss = wpa_bss_update(wpa_s, bss, res, fetch_time);
if (wpa_s->last_scan_res) {
unsigned int i;
for (i = 0; i < wpa_s->last_scan_res_used; i++) {
if (bss == wpa_s->last_scan_res[i]) {
/* Already in the list */
return;
}
}
}
}
if (bss == NULL)
return;
if (wpa_s->last_scan_res_used >= wpa_s->last_scan_res_size) {
struct wpa_bss **n;
unsigned int siz;
if (wpa_s->last_scan_res_size == 0)
siz = 32;
else
siz = wpa_s->last_scan_res_size * 2;
n = os_realloc_array(wpa_s->last_scan_res, siz,
sizeof(struct wpa_bss *));
if (n == NULL)
return;
wpa_s->last_scan_res = n;
wpa_s->last_scan_res_size = siz;
}
if (wpa_s->last_scan_res)
wpa_s->last_scan_res[wpa_s->last_scan_res_used++] = bss;
}
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;
}
/**
* wpa_bss_update_end - End a BSS table update from scan results
* @wpa_s: Pointer to wpa_supplicant data
* @info: Information about scan parameters
* @new_scan: Whether this update round was based on a new scan
*
* This function is called at the end of each BSS table update round for new
* scan results. The start of the update was indicated with a call to
* wpa_bss_update_start().
*/
void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info,
int new_scan)
{
struct wpa_bss *bss, *n;
os_get_reltime(&wpa_s->last_scan);
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_s->conf->bss_expiration_scan_count) {
wpa_bss_remove(wpa_s, bss, "no match in scan");
}
}
wpa_printf(MSG_DEBUG, "BSS: last_scan_res_used=%u/%u",
wpa_s->last_scan_res_used, wpa_s->last_scan_res_size);
}
/**
* wpa_bss_flush_by_age - Flush old BSS entries
* @wpa_s: Pointer to wpa_supplicant data
* @age: Maximum entry age in seconds
*
* Remove BSS entries that have not been updated during the last @age seconds.
*/
void wpa_bss_flush_by_age(struct wpa_supplicant *wpa_s, int age)
{
struct wpa_bss *bss, *n;
struct os_reltime t;
if (dl_list_empty(&wpa_s->bss))
return;
os_get_reltime(&t);
t.sec -= 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_reltime_before(&bss->last_update, &t)) {
wpa_bss_remove(wpa_s, bss, __func__);
} else
break;
}
}
static void wpa_bss_timeout(void *eloop_ctx, void *timeout_ctx)
{
struct wpa_supplicant *wpa_s = eloop_ctx;
wpa_bss_flush_by_age(wpa_s, wpa_s->conf->bss_expiration_age);
eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
wpa_bss_timeout, wpa_s, NULL);
}
/**
* wpa_bss_init - Initialize BSS table
* @wpa_s: Pointer to wpa_supplicant data
* Returns: 0 on success, -1 on failure
*
* This prepares BSS table lists and timer for periodic updates. The BSS table
* is deinitialized with wpa_bss_deinit() once not needed anymore.
*/
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;
}
/**
* wpa_bss_flush - Flush all unused BSS entries
* @wpa_s: Pointer to wpa_supplicant data
*/
void wpa_bss_flush(struct wpa_supplicant *wpa_s)
{
struct wpa_bss *bss, *n;
wpa_s->clear_driver_scan_cache = 1;
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) {
if (wpa_bss_in_use(wpa_s, bss))
continue;
wpa_bss_remove(wpa_s, bss, __func__);
}
}
/**
* wpa_bss_deinit - Deinitialize BSS table
* @wpa_s: Pointer to wpa_supplicant data
*/
void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
{
eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL);
wpa_bss_flush(wpa_s);
}
/**
* wpa_bss_get_bssid - Fetch a BSS table entry based on BSSID
* @wpa_s: Pointer to wpa_supplicant data
* @bssid: BSSID
* Returns: Pointer to the BSS entry or %NULL if not found
*/
struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
const u8 *bssid)
{
struct wpa_bss *bss;
if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
return NULL;
dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
return bss;
}
return NULL;
}
/**
* wpa_bss_get_bssid_latest - Fetch the latest BSS table entry based on BSSID
* @wpa_s: Pointer to wpa_supplicant data
* @bssid: BSSID
* Returns: Pointer to the BSS entry or %NULL if not found
*
* This function is like wpa_bss_get_bssid(), but full BSS table is iterated to
* find the entry that has the most recent update. This can help in finding the
* correct entry in cases where the SSID of the AP may have changed recently
* (e.g., in WPS reconfiguration cases).
*/
struct wpa_bss * wpa_bss_get_bssid_latest(struct wpa_supplicant *wpa_s,
const u8 *bssid)
{
struct wpa_bss *bss, *found = NULL;
if (!wpa_supplicant_filter_bssid_match(wpa_s, bssid))
return NULL;
dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
if (os_memcmp(bss->bssid, bssid, ETH_ALEN) != 0)
continue;
if (found == NULL ||
os_reltime_before(&found->last_update, &bss->last_update))
found = bss;
}
return found;
}
#ifdef CONFIG_P2P
/**
* wpa_bss_get_p2p_dev_addr - Fetch a BSS table entry based on P2P Device Addr
* @wpa_s: Pointer to wpa_supplicant data
* @dev_addr: P2P Device Address of the GO
* Returns: Pointer to the BSS entry or %NULL if not found
*/
struct wpa_bss * wpa_bss_get_p2p_dev_addr(struct wpa_supplicant *wpa_s,
const u8 *dev_addr)
{
struct wpa_bss *bss;
dl_list_for_each_reverse(bss, &wpa_s->bss, struct wpa_bss, list) {
u8 addr[ETH_ALEN];
if (p2p_parse_dev_addr((const u8 *) (bss + 1), bss->ie_len,
addr) == 0 &&
os_memcmp(addr, dev_addr, ETH_ALEN) == 0)
return bss;
}
return NULL;
}
#endif /* CONFIG_P2P */
/**
* wpa_bss_get_id - Fetch a BSS table entry based on identifier
* @wpa_s: Pointer to wpa_supplicant data
* @id: Unique identifier (struct wpa_bss::id) assigned for the entry
* Returns: Pointer to the BSS entry or %NULL if not found
*/
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;
}
/**
* wpa_bss_get_id_range - Fetch a BSS table entry based on identifier range
* @wpa_s: Pointer to wpa_supplicant data
* @idf: Smallest allowed identifier assigned for the entry
* @idf: Largest allowed identifier assigned for the entry
* Returns: Pointer to the BSS entry or %NULL if not found
*
* This function is similar to wpa_bss_get_id() but allows a BSS entry with the
* smallest id value to be fetched within the specified range without the
* caller having to know the exact id.
*/
struct wpa_bss * wpa_bss_get_id_range(struct wpa_supplicant *wpa_s,
unsigned int idf, unsigned int idl)
{
struct wpa_bss *bss;
dl_list_for_each(bss, &wpa_s->bss_id, struct wpa_bss, list_id) {
if (bss->id >= idf && bss->id <= idl)
return bss;
}
return NULL;
}
/**
* wpa_bss_get_ie - Fetch a specified information element from a BSS entry
* @bss: BSS table entry
* @ie: Information element identitifier (WLAN_EID_*)
* Returns: Pointer to the information element (id field) or %NULL if not found
*
* This function returns the first matching information element in the BSS
* entry.
*/
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;
}
/**
* wpa_bss_get_vendor_ie - Fetch a vendor information element from a BSS entry
* @bss: BSS table entry
* @vendor_type: Vendor type (four octets starting the IE payload)
* Returns: Pointer to the information element (id field) or %NULL if not found
*
* This function returns the first matching information element in the BSS
* entry.
*/
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;
}
/**
* wpa_bss_get_vendor_ie_beacon - Fetch a vendor information from a BSS entry
* @bss: BSS table entry
* @vendor_type: Vendor type (four octets starting the IE payload)
* Returns: Pointer to the information element (id field) or %NULL if not found
*
* This function returns the first matching information element in the BSS
* entry.
*
* This function is like wpa_bss_get_vendor_ie(), but uses IE buffer only
* from Beacon frames instead of either Beacon or Probe Response frames.
*/
const u8 * wpa_bss_get_vendor_ie_beacon(const struct wpa_bss *bss,
u32 vendor_type)
{
const u8 *end, *pos;
if (bss->beacon_ie_len == 0)
return NULL;
pos = (const u8 *) (bss + 1);
pos += bss->ie_len;
end = pos + bss->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]))
return pos;
pos += 2 + pos[1];
}
return NULL;
}
/**
* wpa_bss_get_vendor_ie_multi - Fetch vendor IE data from a BSS entry
* @bss: BSS table entry
* @vendor_type: Vendor type (four octets starting the IE payload)
* Returns: Pointer to the information element payload or %NULL if not found
*
* This function returns concatenated payload of possibly fragmented vendor
* specific information elements in the BSS entry. The caller is responsible for
* freeing the returned buffer.
*/
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;
}
/**
* wpa_bss_get_vendor_ie_multi_beacon - Fetch vendor IE data from a BSS entry
* @bss: BSS table entry
* @vendor_type: Vendor type (four octets starting the IE payload)
* Returns: Pointer to the information element payload or %NULL if not found
*
* This function returns concatenated payload of possibly fragmented vendor
* specific information elements in the BSS entry. The caller is responsible for
* freeing the returned buffer.
*
* This function is like wpa_bss_get_vendor_ie_multi(), but uses IE buffer only
* from Beacon frames instead of either Beacon or Probe Response frames.
*/
struct wpabuf * wpa_bss_get_vendor_ie_multi_beacon(const struct wpa_bss *bss,
u32 vendor_type)
{
struct wpabuf *buf;
const u8 *end, *pos;
buf = wpabuf_alloc(bss->beacon_ie_len);
if (buf == NULL)
return NULL;
pos = (const u8 *) (bss + 1);
pos += bss->ie_len;
end = pos + bss->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;
}
/**
* wpa_bss_get_max_rate - Get maximum legacy TX rate supported in a BSS
* @bss: BSS table entry
* Returns: Maximum legacy rate in units of 500 kbps
*/
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;
}
/**
* wpa_bss_get_bit_rates - Get legacy TX rates supported in a BSS
* @bss: BSS table entry
* @rates: Buffer for returning a pointer to the rates list (units of 500 kbps)
* Returns: number of legacy TX rates or -1 on failure
*
* The caller is responsible for freeing the returned buffer with os_free() in
* case of success.
*/
int wpa_bss_get_bit_rates(const struct wpa_bss *bss, u8 **rates)
{
const u8 *ie, *ie2;
int i, j;
unsigned int len;
u8 *r;
ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
ie2 = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
len = (ie ? ie[1] : 0) + (ie2 ? ie2[1] : 0);
r = os_malloc(len);
if (!r)
return -1;
for (i = 0; ie && i < ie[1]; i++)
r[i] = ie[i + 2] & 0x7f;
for (j = 0; ie2 && j < ie2[1]; j++)
r[i + j] = ie2[j + 2] & 0x7f;
*rates = r;
return len;
}