| Current Path : /usr/src/contrib/wpa/wpa_supplicant/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/contrib/wpa/wpa_supplicant/bss.c |
/*
* BSS table
* Copyright (c) 2009-2010, Jouni Malinen <j@w1.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include "utils/includes.h"
#include "utils/common.h"
#include "utils/eloop.h"
#include "common/ieee802_11_defs.h"
#include "drivers/driver.h"
#include "wpa_supplicant_i.h"
#include "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
/**
* WPA_BSS_EXPIRATION_AGE - BSS entry age after which it can be expired
*
* This value control the time in seconds after which a BSS entry gets removed
* if it has not been updated or is not in use.
*/
#define WPA_BSS_EXPIRATION_AGE 180
/**
* WPA_BSS_EXPIRATION_SCAN_COUNT - Expire BSS after number of scans
*
* If the BSS entry has not been seen in this many scans, it will be removed.
* Value 1 means that the entry is removed after the first scan without the
* BSSID being seen. Larger values can be used to avoid BSS entries
* disappearing if they are not visible in every scan (e.g., low signal quality
* or interference).
*/
#define WPA_BSS_EXPIRATION_SCAN_COUNT 2
#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_printf(MSG_DEBUG, "BSS: Remove id %u BSSID " MACSTR " SSID '%s'",
bss->id, MAC2STR(bss->bssid),
wpa_ssid_txt(bss->ssid, bss->ssid_len));
wpas_notify_bss_removed(wpa_s, bss->bssid, bss->id);
os_free(bss);
}
struct wpa_bss * wpa_bss_get(struct wpa_supplicant *wpa_s, const u8 *bssid,
const u8 *ssid, size_t ssid_len)
{
struct wpa_bss *bss;
dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0 &&
bss->ssid_len == ssid_len &&
os_memcmp(bss->ssid, ssid, ssid_len) == 0)
return bss;
}
return NULL;
}
static void wpa_bss_copy_res(struct wpa_bss *dst, struct wpa_scan_res *src)
{
os_time_t usec;
dst->flags = src->flags;
os_memcpy(dst->bssid, src->bssid, ETH_ALEN);
dst->freq = src->freq;
dst->beacon_int = src->beacon_int;
dst->caps = src->caps;
dst->qual = src->qual;
dst->noise = src->noise;
dst->level = src->level;
dst->tsf = src->tsf;
os_get_time(&dst->last_update);
dst->last_update.sec -= src->age / 1000;
usec = (src->age % 1000) * 1000;
if (dst->last_update.usec < usec) {
dst->last_update.sec--;
dst->last_update.usec += 1000000;
}
dst->last_update.usec -= usec;
}
static void wpa_bss_add(struct wpa_supplicant *wpa_s,
const u8 *ssid, size_t ssid_len,
struct wpa_scan_res *res)
{
struct wpa_bss *bss;
bss = os_zalloc(sizeof(*bss) + res->ie_len + 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_printf(MSG_DEBUG, "BSS: Add new id %u BSSID " MACSTR " SSID '%s'",
bss->id, MAC2STR(bss->bssid), wpa_ssid_txt(ssid, ssid_len));
wpas_notify_bss_added(wpa_s, bss->bssid, bss->id);
if (wpa_s->num_bss > wpa_s->conf->bss_max_count) {
/* Remove the oldest entry */
wpa_bss_remove(wpa_s, dl_list_first(&wpa_s->bss,
struct wpa_bss, list));
}
}
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;
}
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_printf(MSG_DEBUG, "BSS: Start scan result update %u",
wpa_s->bss_update_idx);
}
void wpa_bss_update_scan_res(struct wpa_supplicant *wpa_s,
struct wpa_scan_res *res)
{
const u8 *ssid;
struct wpa_bss *bss;
ssid = wpa_scan_get_ie(res, WLAN_EID_SSID);
if (ssid == NULL) {
wpa_printf(MSG_DEBUG, "BSS: No SSID IE included for " MACSTR,
MAC2STR(res->bssid));
return;
}
if (ssid[1] > 32) {
wpa_printf(MSG_DEBUG, "BSS: Too long SSID IE included for "
MACSTR, MAC2STR(res->bssid));
return;
}
/* TODO: add option for ignoring BSSes we are not interested in
* (to save memory) */
bss = wpa_bss_get(wpa_s, res->bssid, ssid + 2, ssid[1]);
if (bss == NULL)
wpa_bss_add(wpa_s, ssid + 2, ssid[1], res);
else
wpa_bss_update(wpa_s, bss, res);
}
static int wpa_bss_included_in_scan(const struct wpa_bss *bss,
const struct scan_info *info)
{
int found;
size_t i;
if (info == NULL)
return 1;
if (info->num_freqs) {
found = 0;
for (i = 0; i < info->num_freqs; i++) {
if (bss->freq == info->freqs[i]) {
found = 1;
break;
}
}
if (!found)
return 0;
}
if (info->num_ssids) {
found = 0;
for (i = 0; i < info->num_ssids; i++) {
const struct wpa_driver_scan_ssid *s = &info->ssids[i];
if ((s->ssid == NULL || s->ssid_len == 0) ||
(s->ssid_len == bss->ssid_len &&
os_memcmp(s->ssid, bss->ssid, bss->ssid_len) ==
0)) {
found = 1;
break;
}
}
if (!found)
return 0;
}
return 1;
}
void wpa_bss_update_end(struct wpa_supplicant *wpa_s, struct scan_info *info,
int new_scan)
{
struct wpa_bss *bss, *n;
if (!new_scan)
return; /* do not expire entries without new scan */
dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
if (wpa_bss_in_use(wpa_s, bss))
continue;
if (!wpa_bss_included_in_scan(bss, info))
continue; /* expire only BSSes that were scanned */
if (bss->last_update_idx < wpa_s->bss_update_idx)
bss->scan_miss_count++;
if (bss->scan_miss_count >= WPA_BSS_EXPIRATION_SCAN_COUNT) {
wpa_printf(MSG_DEBUG, "BSS: Expire BSS %u due to no "
"match in scan", bss->id);
wpa_bss_remove(wpa_s, bss);
}
}
}
static void wpa_bss_timeout(void *eloop_ctx, void *timeout_ctx)
{
struct wpa_supplicant *wpa_s = eloop_ctx;
struct wpa_bss *bss, *n;
struct os_time t;
if (dl_list_empty(&wpa_s->bss))
return;
os_get_time(&t);
t.sec -= WPA_BSS_EXPIRATION_AGE;
dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list) {
if (wpa_bss_in_use(wpa_s, bss))
continue;
if (os_time_before(&bss->last_update, &t)) {
wpa_printf(MSG_DEBUG, "BSS: Expire BSS %u due to age",
bss->id);
wpa_bss_remove(wpa_s, bss);
} else
break;
}
eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
wpa_bss_timeout, wpa_s, NULL);
}
int wpa_bss_init(struct wpa_supplicant *wpa_s)
{
dl_list_init(&wpa_s->bss);
dl_list_init(&wpa_s->bss_id);
eloop_register_timeout(WPA_BSS_EXPIRATION_PERIOD, 0,
wpa_bss_timeout, wpa_s, NULL);
return 0;
}
void wpa_bss_deinit(struct wpa_supplicant *wpa_s)
{
struct wpa_bss *bss, *n;
eloop_cancel_timeout(wpa_bss_timeout, wpa_s, NULL);
if (wpa_s->bss.next == NULL)
return; /* BSS table not yet initialized */
dl_list_for_each_safe(bss, n, &wpa_s->bss, struct wpa_bss, list)
wpa_bss_remove(wpa_s, bss);
}
struct wpa_bss * wpa_bss_get_bssid(struct wpa_supplicant *wpa_s,
const u8 *bssid)
{
struct wpa_bss *bss;
dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
if (os_memcmp(bss->bssid, bssid, ETH_ALEN) == 0)
return bss;
}
return NULL;
}
struct wpa_bss * wpa_bss_get_id(struct wpa_supplicant *wpa_s, unsigned int id)
{
struct wpa_bss *bss;
dl_list_for_each(bss, &wpa_s->bss, struct wpa_bss, list) {
if (bss->id == id)
return bss;
}
return NULL;
}
const u8 * wpa_bss_get_ie(const struct wpa_bss *bss, u8 ie)
{
const u8 *end, *pos;
pos = (const u8 *) (bss + 1);
end = pos + bss->ie_len;
while (pos + 1 < end) {
if (pos + 2 + pos[1] > end)
break;
if (pos[0] == ie)
return pos;
pos += 2 + pos[1];
}
return NULL;
}
const u8 * wpa_bss_get_vendor_ie(const struct wpa_bss *bss, u32 vendor_type)
{
const u8 *end, *pos;
pos = (const u8 *) (bss + 1);
end = pos + bss->ie_len;
while (pos + 1 < end) {
if (pos + 2 + pos[1] > end)
break;
if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
vendor_type == WPA_GET_BE32(&pos[2]))
return pos;
pos += 2 + pos[1];
}
return NULL;
}
struct wpabuf * wpa_bss_get_vendor_ie_multi(const struct wpa_bss *bss,
u32 vendor_type)
{
struct wpabuf *buf;
const u8 *end, *pos;
buf = wpabuf_alloc(bss->ie_len);
if (buf == NULL)
return NULL;
pos = (const u8 *) (bss + 1);
end = pos + bss->ie_len;
while (pos + 1 < end) {
if (pos + 2 + pos[1] > end)
break;
if (pos[0] == WLAN_EID_VENDOR_SPECIFIC && pos[1] >= 4 &&
vendor_type == WPA_GET_BE32(&pos[2]))
wpabuf_put_data(buf, pos + 2 + 4, pos[1] - 4);
pos += 2 + pos[1];
}
if (wpabuf_len(buf) == 0) {
wpabuf_free(buf);
buf = NULL;
}
return buf;
}
int wpa_bss_get_max_rate(const struct wpa_bss *bss)
{
int rate = 0;
const u8 *ie;
int i;
ie = wpa_bss_get_ie(bss, WLAN_EID_SUPP_RATES);
for (i = 0; ie && i < ie[1]; i++) {
if ((ie[i + 2] & 0x7f) > rate)
rate = ie[i + 2] & 0x7f;
}
ie = wpa_bss_get_ie(bss, WLAN_EID_EXT_SUPP_RATES);
for (i = 0; ie && i < ie[1]; i++) {
if ((ie[i + 2] & 0x7f) > rate)
rate = ie[i + 2] & 0x7f;
}
return rate;
}
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;
}