hostap/wpa_supplicant/bss.c
Jouni Malinen 0a70f34f22 P2P: Allow BSS entry to be fetched based on GO P2P Device Address
"BSS p2p_dev_addr=<P2P Device Address>" can now be used to fetch a
specific BSS entry based on the P2P Device Address of the GO to avoid
having to iterate through the full BSS table when an external program
needs to figure out whether a specific peer is currently operating as
a GO.

Signed-hostap: Jouni Malinen <jouni@qca.qualcomm.com>
2012-02-07 16:23:21 +02:00

687 lines
16 KiB
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 "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_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_dbg(wpa_s, 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);
#ifdef CONFIG_INTERWORKING
wpabuf_free(bss->anqp_venue_name);
wpabuf_free(bss->anqp_network_auth_type);
wpabuf_free(bss->anqp_roaming_consortium);
wpabuf_free(bss->anqp_ip_addr_type_availability);
wpabuf_free(bss->anqp_nai_realm);
wpabuf_free(bss->anqp_3gpp);
wpabuf_free(bss->anqp_domain_name);
#endif /* CONFIG_INTERWORKING */
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 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_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);
return 0;
}
}
return -1;
}
static void wpa_bss_remove_oldest(struct wpa_supplicant *wpa_s)
{
/*
* Remove the oldest entry that does not match with any configured
* network.
*/
if (wpa_bss_remove_oldest_unknown(wpa_s) == 0)
return;
/*
* Remove the oldest entry since no better candidate for removal was
* found.
*/
wpa_bss_remove(wpa_s, dl_list_first(&wpa_s->bss,
struct wpa_bss, list));
}
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 + res->beacon_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;
bss->beacon_ie_len = res->beacon_ie_len;
os_memcpy(bss + 1, res + 1, res->ie_len + res->beacon_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_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);
if (wpa_s->num_bss > wpa_s->conf->bss_max_count)
wpa_bss_remove_oldest(wpa_s);
}
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 void wpa_bss_update(struct wpa_supplicant *wpa_s, struct wpa_bss *bss,
struct wpa_scan_res *res)
{
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);
/* Move the entry to the end of the list */
dl_list_del(&bss->list);
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) {
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);
}
dl_list_add_tail(&wpa_s->bss, &bss->list);
notify_bss_changes(wpa_s, changes, bss);
}
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_dbg(wpa_s, 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, *p2p;
struct wpa_bss *bss;
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);
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)
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_s->conf->bss_expiration_scan_count) {
wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Expire BSS %u due to "
"no match in scan", bss->id);
wpa_bss_remove(wpa_s, bss);
}
}
}
void wpa_bss_flush_by_age(struct wpa_supplicant *wpa_s, int age)
{
struct wpa_bss *bss, *n;
struct os_time t;
if (dl_list_empty(&wpa_s->bss))
return;
os_get_time(&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_time_before(&bss->last_update, &t)) {
wpa_dbg(wpa_s, MSG_DEBUG, "BSS: Expire BSS %u due to "
"age", bss->id);
wpa_bss_remove(wpa_s, bss);
} 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);
}
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_flush(struct wpa_supplicant *wpa_s)
{
struct wpa_bss *bss, *n;
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);
}
}
void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
{
eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL);
wpa_bss_flush(wpa_s);
}
struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
const u8 *bssid)
{
struct wpa_bss *bss;
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;
}
#ifdef CONFIG_P2P
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 */
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;
}
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;
}