hostap/src/ap/ap_list.c
Luciano Coelho 370b076197 hostapd: Only update already-set beacons when processing OLBC
When hostapd is about to start an AP using HT40, it starts a scan to
check whether it is allowed or not. If OLBC is detected before the
scan has completed, it sets the beacons prematurely.

To fix this, instead of setting all beacons when OLBC is detected,
only update the ones that have already been started.

Signed-off-by: Luciano Coelho <coelho@ti.com>
2012-04-01 18:12:04 +03:00

391 lines
8.5 KiB
C

/*
* hostapd / AP table
* Copyright (c) 2002-2009, Jouni Malinen <j@w1.fi>
* Copyright (c) 2003-2004, Instant802 Networks, Inc.
* Copyright (c) 2006, Devicescape Software, Inc.
*
* 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 "common/ieee802_11_common.h"
#include "drivers/driver.h"
#include "hostapd.h"
#include "ap_config.h"
#include "ieee802_11.h"
#include "sta_info.h"
#include "beacon.h"
#include "ap_list.h"
/* AP list is a double linked list with head->prev pointing to the end of the
* list and tail->next = NULL. Entries are moved to the head of the list
* whenever a beacon has been received from the AP in question. The tail entry
* in this link will thus be the least recently used entry. */
static int ap_list_beacon_olbc(struct hostapd_iface *iface, struct ap_info *ap)
{
int i;
if (iface->current_mode->mode != HOSTAPD_MODE_IEEE80211G ||
iface->conf->channel != ap->channel)
return 0;
if (ap->erp != -1 && (ap->erp & ERP_INFO_NON_ERP_PRESENT))
return 1;
for (i = 0; i < WLAN_SUPP_RATES_MAX; i++) {
int rate = (ap->supported_rates[i] & 0x7f) * 5;
if (rate == 60 || rate == 90 || rate > 110)
return 0;
}
return 1;
}
struct ap_info * ap_get_ap(struct hostapd_iface *iface, const u8 *ap)
{
struct ap_info *s;
s = iface->ap_hash[STA_HASH(ap)];
while (s != NULL && os_memcmp(s->addr, ap, ETH_ALEN) != 0)
s = s->hnext;
return s;
}
static void ap_ap_list_add(struct hostapd_iface *iface, struct ap_info *ap)
{
if (iface->ap_list) {
ap->prev = iface->ap_list->prev;
iface->ap_list->prev = ap;
} else
ap->prev = ap;
ap->next = iface->ap_list;
iface->ap_list = ap;
}
static void ap_ap_list_del(struct hostapd_iface *iface, struct ap_info *ap)
{
if (iface->ap_list == ap)
iface->ap_list = ap->next;
else
ap->prev->next = ap->next;
if (ap->next)
ap->next->prev = ap->prev;
else if (iface->ap_list)
iface->ap_list->prev = ap->prev;
}
static void ap_ap_iter_list_add(struct hostapd_iface *iface,
struct ap_info *ap)
{
if (iface->ap_iter_list) {
ap->iter_prev = iface->ap_iter_list->iter_prev;
iface->ap_iter_list->iter_prev = ap;
} else
ap->iter_prev = ap;
ap->iter_next = iface->ap_iter_list;
iface->ap_iter_list = ap;
}
static void ap_ap_iter_list_del(struct hostapd_iface *iface,
struct ap_info *ap)
{
if (iface->ap_iter_list == ap)
iface->ap_iter_list = ap->iter_next;
else
ap->iter_prev->iter_next = ap->iter_next;
if (ap->iter_next)
ap->iter_next->iter_prev = ap->iter_prev;
else if (iface->ap_iter_list)
iface->ap_iter_list->iter_prev = ap->iter_prev;
}
static void ap_ap_hash_add(struct hostapd_iface *iface, struct ap_info *ap)
{
ap->hnext = iface->ap_hash[STA_HASH(ap->addr)];
iface->ap_hash[STA_HASH(ap->addr)] = ap;
}
static void ap_ap_hash_del(struct hostapd_iface *iface, struct ap_info *ap)
{
struct ap_info *s;
s = iface->ap_hash[STA_HASH(ap->addr)];
if (s == NULL) return;
if (os_memcmp(s->addr, ap->addr, ETH_ALEN) == 0) {
iface->ap_hash[STA_HASH(ap->addr)] = s->hnext;
return;
}
while (s->hnext != NULL &&
os_memcmp(s->hnext->addr, ap->addr, ETH_ALEN) != 0)
s = s->hnext;
if (s->hnext != NULL)
s->hnext = s->hnext->hnext;
else
printf("AP: could not remove AP " MACSTR " from hash table\n",
MAC2STR(ap->addr));
}
static void ap_free_ap(struct hostapd_iface *iface, struct ap_info *ap)
{
ap_ap_hash_del(iface, ap);
ap_ap_list_del(iface, ap);
ap_ap_iter_list_del(iface, ap);
iface->num_ap--;
os_free(ap);
}
static void hostapd_free_aps(struct hostapd_iface *iface)
{
struct ap_info *ap, *prev;
ap = iface->ap_list;
while (ap) {
prev = ap;
ap = ap->next;
ap_free_ap(iface, prev);
}
iface->ap_list = NULL;
}
int ap_ap_for_each(struct hostapd_iface *iface,
int (*func)(struct ap_info *s, void *data), void *data)
{
struct ap_info *s;
int ret = 0;
s = iface->ap_list;
while (s) {
ret = func(s, data);
if (ret)
break;
s = s->next;
}
return ret;
}
static struct ap_info * ap_ap_add(struct hostapd_iface *iface, const u8 *addr)
{
struct ap_info *ap;
ap = os_zalloc(sizeof(struct ap_info));
if (ap == NULL)
return NULL;
/* initialize AP info data */
os_memcpy(ap->addr, addr, ETH_ALEN);
ap_ap_list_add(iface, ap);
iface->num_ap++;
ap_ap_hash_add(iface, ap);
ap_ap_iter_list_add(iface, ap);
if (iface->num_ap > iface->conf->ap_table_max_size && ap != ap->prev) {
wpa_printf(MSG_DEBUG, "Removing the least recently used AP "
MACSTR " from AP table", MAC2STR(ap->prev->addr));
ap_free_ap(iface, ap->prev);
}
return ap;
}
void ap_list_process_beacon(struct hostapd_iface *iface,
const struct ieee80211_mgmt *mgmt,
struct ieee802_11_elems *elems,
struct hostapd_frame_info *fi)
{
struct ap_info *ap;
struct os_time now;
int new_ap = 0;
size_t len;
int set_beacon = 0;
if (iface->conf->ap_table_max_size < 1)
return;
ap = ap_get_ap(iface, mgmt->bssid);
if (!ap) {
ap = ap_ap_add(iface, mgmt->bssid);
if (!ap) {
printf("Failed to allocate AP information entry\n");
return;
}
new_ap = 1;
}
ap->beacon_int = le_to_host16(mgmt->u.beacon.beacon_int);
ap->capability = le_to_host16(mgmt->u.beacon.capab_info);
if (elems->ssid) {
len = elems->ssid_len;
if (len >= sizeof(ap->ssid))
len = sizeof(ap->ssid) - 1;
os_memcpy(ap->ssid, elems->ssid, len);
ap->ssid[len] = '\0';
ap->ssid_len = len;
}
os_memset(ap->supported_rates, 0, WLAN_SUPP_RATES_MAX);
len = 0;
if (elems->supp_rates) {
len = elems->supp_rates_len;
if (len > WLAN_SUPP_RATES_MAX)
len = WLAN_SUPP_RATES_MAX;
os_memcpy(ap->supported_rates, elems->supp_rates, len);
}
if (elems->ext_supp_rates) {
int len2;
if (len + elems->ext_supp_rates_len > WLAN_SUPP_RATES_MAX)
len2 = WLAN_SUPP_RATES_MAX - len;
else
len2 = elems->ext_supp_rates_len;
os_memcpy(ap->supported_rates + len, elems->ext_supp_rates,
len2);
}
ap->wpa = elems->wpa_ie != NULL;
if (elems->erp_info && elems->erp_info_len == 1)
ap->erp = elems->erp_info[0];
else
ap->erp = -1;
if (elems->ds_params && elems->ds_params_len == 1)
ap->channel = elems->ds_params[0];
else if (fi)
ap->channel = fi->channel;
if (elems->ht_capabilities)
ap->ht_support = 1;
else
ap->ht_support = 0;
ap->num_beacons++;
os_get_time(&now);
ap->last_beacon = now.sec;
if (fi)
ap->datarate = fi->datarate;
if (!new_ap && ap != iface->ap_list) {
/* move AP entry into the beginning of the list so that the
* oldest entry is always in the end of the list */
ap_ap_list_del(iface, ap);
ap_ap_list_add(iface, ap);
}
if (!iface->olbc &&
ap_list_beacon_olbc(iface, ap)) {
iface->olbc = 1;
wpa_printf(MSG_DEBUG, "OLBC AP detected: " MACSTR " - enable "
"protection", MAC2STR(ap->addr));
set_beacon++;
}
#ifdef CONFIG_IEEE80211N
if (!iface->olbc_ht && !ap->ht_support) {
iface->olbc_ht = 1;
hostapd_ht_operation_update(iface);
wpa_printf(MSG_DEBUG, "OLBC HT AP detected: " MACSTR
" - enable protection", MAC2STR(ap->addr));
set_beacon++;
}
#endif /* CONFIG_IEEE80211N */
if (set_beacon)
ieee802_11_update_beacons(iface);
}
static void ap_list_timer(void *eloop_ctx, void *timeout_ctx)
{
struct hostapd_iface *iface = eloop_ctx;
struct os_time now;
struct ap_info *ap;
int set_beacon = 0;
eloop_register_timeout(10, 0, ap_list_timer, iface, NULL);
if (!iface->ap_list)
return;
os_get_time(&now);
while (iface->ap_list) {
ap = iface->ap_list->prev;
if (ap->last_beacon + iface->conf->ap_table_expiration_time >=
now.sec)
break;
ap_free_ap(iface, ap);
}
if (iface->olbc || iface->olbc_ht) {
int olbc = 0;
int olbc_ht = 0;
ap = iface->ap_list;
while (ap && (olbc == 0 || olbc_ht == 0)) {
if (ap_list_beacon_olbc(iface, ap))
olbc = 1;
if (!ap->ht_support)
olbc_ht = 1;
ap = ap->next;
}
if (!olbc && iface->olbc) {
wpa_printf(MSG_DEBUG, "OLBC not detected anymore");
iface->olbc = 0;
set_beacon++;
}
#ifdef CONFIG_IEEE80211N
if (!olbc_ht && iface->olbc_ht) {
wpa_printf(MSG_DEBUG, "OLBC HT not detected anymore");
iface->olbc_ht = 0;
hostapd_ht_operation_update(iface);
set_beacon++;
}
#endif /* CONFIG_IEEE80211N */
}
if (set_beacon)
ieee802_11_update_beacons(iface);
}
int ap_list_init(struct hostapd_iface *iface)
{
eloop_register_timeout(10, 0, ap_list_timer, iface, NULL);
return 0;
}
void ap_list_deinit(struct hostapd_iface *iface)
{
eloop_cancel_timeout(ap_list_timer, iface, NULL);
hostapd_free_aps(iface);
}