hostap/wpa_supplicant/scan.c
Johannes Berg acb69cec6f wpa_supplicant: Use monotonic time for RX/BSS times
The BSS table, scan timeout, and related functionality should use
monotonic time since they care about relative values (age) only.
Unfortunately, these are all connected, so the patch can't be split
further. Another problem with this is that it changes the driver wrapper
API. Though, it seems only the test driver is using this.

Signed-hostap: Johannes Berg <johannes.berg@intel.com>
2013-12-24 07:27:02 +02:00

1732 lines
46 KiB
C

/*
* WPA Supplicant - Scanning
* Copyright (c) 2003-2012, 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 "common/wpa_ctrl.h"
#include "config.h"
#include "wpa_supplicant_i.h"
#include "driver_i.h"
#include "wps_supplicant.h"
#include "p2p_supplicant.h"
#include "p2p/p2p.h"
#include "hs20_supplicant.h"
#include "notify.h"
#include "bss.h"
#include "gas_query.h"
#include "scan.h"
static void wpa_supplicant_gen_assoc_event(struct wpa_supplicant *wpa_s)
{
struct wpa_ssid *ssid;
union wpa_event_data data;
ssid = wpa_supplicant_get_ssid(wpa_s);
if (ssid == NULL)
return;
if (wpa_s->current_ssid == NULL) {
wpa_s->current_ssid = ssid;
if (wpa_s->current_ssid != NULL)
wpas_notify_network_changed(wpa_s);
}
wpa_supplicant_initiate_eapol(wpa_s);
wpa_dbg(wpa_s, MSG_DEBUG, "Already associated with a configured "
"network - generating associated event");
os_memset(&data, 0, sizeof(data));
wpa_supplicant_event(wpa_s, EVENT_ASSOC, &data);
}
#ifdef CONFIG_WPS
static int wpas_wps_in_use(struct wpa_supplicant *wpa_s,
enum wps_request_type *req_type)
{
struct wpa_ssid *ssid;
int wps = 0;
for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
if (!(ssid->key_mgmt & WPA_KEY_MGMT_WPS))
continue;
wps = 1;
*req_type = wpas_wps_get_req_type(ssid);
if (!ssid->eap.phase1)
continue;
if (os_strstr(ssid->eap.phase1, "pbc=1"))
return 2;
}
#ifdef CONFIG_P2P
if (!wpa_s->global->p2p_disabled && wpa_s->global->p2p &&
!wpa_s->conf->p2p_disabled) {
wpa_s->wps->dev.p2p = 1;
if (!wps) {
wps = 1;
*req_type = WPS_REQ_ENROLLEE_INFO;
}
}
#endif /* CONFIG_P2P */
return wps;
}
#endif /* CONFIG_WPS */
/**
* wpa_supplicant_enabled_networks - Check whether there are enabled networks
* @wpa_s: Pointer to wpa_supplicant data
* Returns: 0 if no networks are enabled, >0 if networks are enabled
*
* This function is used to figure out whether any networks (or Interworking
* with enabled credentials and auto_interworking) are present in the current
* configuration.
*/
int wpa_supplicant_enabled_networks(struct wpa_supplicant *wpa_s)
{
struct wpa_ssid *ssid = wpa_s->conf->ssid;
int count = 0, disabled = 0;
while (ssid) {
if (!wpas_network_disabled(wpa_s, ssid))
count++;
else
disabled++;
ssid = ssid->next;
}
if (wpa_s->conf->cred && wpa_s->conf->interworking &&
wpa_s->conf->auto_interworking)
count++;
if (count == 0 && disabled > 0) {
wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks (%d disabled "
"networks)", disabled);
}
return count;
}
static void wpa_supplicant_assoc_try(struct wpa_supplicant *wpa_s,
struct wpa_ssid *ssid)
{
while (ssid) {
if (!wpas_network_disabled(wpa_s, ssid))
break;
ssid = ssid->next;
}
/* ap_scan=2 mode - try to associate with each SSID. */
if (ssid == NULL) {
wpa_dbg(wpa_s, MSG_DEBUG, "wpa_supplicant_assoc_try: Reached "
"end of scan list - go back to beginning");
wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
wpa_supplicant_req_scan(wpa_s, 0, 0);
return;
}
if (ssid->next) {
/* Continue from the next SSID on the next attempt. */
wpa_s->prev_scan_ssid = ssid;
} else {
/* Start from the beginning of the SSID list. */
wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
}
wpa_supplicant_associate(wpa_s, NULL, ssid);
}
static int int_array_len(const int *a)
{
int i;
for (i = 0; a && a[i]; i++)
;
return i;
}
static void int_array_concat(int **res, const int *a)
{
int reslen, alen, i;
int *n;
reslen = int_array_len(*res);
alen = int_array_len(a);
n = os_realloc_array(*res, reslen + alen + 1, sizeof(int));
if (n == NULL) {
os_free(*res);
*res = NULL;
return;
}
for (i = 0; i <= alen; i++)
n[reslen + i] = a[i];
*res = n;
}
static int freq_cmp(const void *a, const void *b)
{
int _a = *(int *) a;
int _b = *(int *) b;
if (_a == 0)
return 1;
if (_b == 0)
return -1;
return _a - _b;
}
static void int_array_sort_unique(int *a)
{
int alen;
int i, j;
if (a == NULL)
return;
alen = int_array_len(a);
qsort(a, alen, sizeof(int), freq_cmp);
i = 0;
j = 1;
while (a[i] && a[j]) {
if (a[i] == a[j]) {
j++;
continue;
}
a[++i] = a[j++];
}
if (a[i])
i++;
a[i] = 0;
}
/**
* wpa_supplicant_trigger_scan - Request driver to start a scan
* @wpa_s: Pointer to wpa_supplicant data
* @params: Scan parameters
* Returns: 0 on success, -1 on failure
*/
int wpa_supplicant_trigger_scan(struct wpa_supplicant *wpa_s,
struct wpa_driver_scan_params *params)
{
int ret;
wpa_supplicant_notify_scanning(wpa_s, 1);
ret = wpa_drv_scan(wpa_s, params);
if (ret) {
wpa_supplicant_notify_scanning(wpa_s, 0);
wpas_notify_scan_done(wpa_s, 0);
} else {
os_get_reltime(&wpa_s->scan_trigger_time);
wpa_s->scan_runs++;
wpa_s->normal_scans++;
}
return ret;
}
static void
wpa_supplicant_delayed_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
{
struct wpa_supplicant *wpa_s = eloop_ctx;
wpa_dbg(wpa_s, MSG_DEBUG, "Starting delayed sched scan");
if (wpa_supplicant_req_sched_scan(wpa_s))
wpa_supplicant_req_scan(wpa_s, 0, 0);
}
static void
wpa_supplicant_sched_scan_timeout(void *eloop_ctx, void *timeout_ctx)
{
struct wpa_supplicant *wpa_s = eloop_ctx;
wpa_dbg(wpa_s, MSG_DEBUG, "Sched scan timeout - stopping it");
wpa_s->sched_scan_timed_out = 1;
wpa_supplicant_cancel_sched_scan(wpa_s);
}
int wpa_supplicant_start_sched_scan(struct wpa_supplicant *wpa_s,
struct wpa_driver_scan_params *params,
int interval)
{
int ret;
wpa_supplicant_notify_scanning(wpa_s, 1);
ret = wpa_drv_sched_scan(wpa_s, params, interval * 1000);
if (ret)
wpa_supplicant_notify_scanning(wpa_s, 0);
else
wpa_s->sched_scanning = 1;
return ret;
}
int wpa_supplicant_stop_sched_scan(struct wpa_supplicant *wpa_s)
{
int ret;
ret = wpa_drv_stop_sched_scan(wpa_s);
if (ret) {
wpa_dbg(wpa_s, MSG_DEBUG, "stopping sched_scan failed!");
/* TODO: what to do if stopping fails? */
return -1;
}
return ret;
}
static struct wpa_driver_scan_filter *
wpa_supplicant_build_filter_ssids(struct wpa_config *conf, size_t *num_ssids)
{
struct wpa_driver_scan_filter *ssids;
struct wpa_ssid *ssid;
size_t count;
*num_ssids = 0;
if (!conf->filter_ssids)
return NULL;
for (count = 0, ssid = conf->ssid; ssid; ssid = ssid->next) {
if (ssid->ssid && ssid->ssid_len)
count++;
}
if (count == 0)
return NULL;
ssids = os_zalloc(count * sizeof(struct wpa_driver_scan_filter));
if (ssids == NULL)
return NULL;
for (ssid = conf->ssid; ssid; ssid = ssid->next) {
if (!ssid->ssid || !ssid->ssid_len)
continue;
os_memcpy(ssids[*num_ssids].ssid, ssid->ssid, ssid->ssid_len);
ssids[*num_ssids].ssid_len = ssid->ssid_len;
(*num_ssids)++;
}
return ssids;
}
static void wpa_supplicant_optimize_freqs(
struct wpa_supplicant *wpa_s, struct wpa_driver_scan_params *params)
{
#ifdef CONFIG_P2P
if (params->freqs == NULL && wpa_s->p2p_in_provisioning &&
wpa_s->go_params) {
/* Optimize provisioning state scan based on GO information */
if (wpa_s->p2p_in_provisioning < 5 &&
wpa_s->go_params->freq > 0) {
wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only GO "
"preferred frequency %d MHz",
wpa_s->go_params->freq);
params->freqs = os_zalloc(2 * sizeof(int));
if (params->freqs)
params->freqs[0] = wpa_s->go_params->freq;
} else if (wpa_s->p2p_in_provisioning < 8 &&
wpa_s->go_params->freq_list[0]) {
wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only common "
"channels");
int_array_concat(&params->freqs,
wpa_s->go_params->freq_list);
if (params->freqs)
int_array_sort_unique(params->freqs);
}
wpa_s->p2p_in_provisioning++;
}
#endif /* CONFIG_P2P */
#ifdef CONFIG_WPS
if (params->freqs == NULL && wpa_s->after_wps && wpa_s->wps_freq) {
/*
* Optimize post-provisioning scan based on channel used
* during provisioning.
*/
wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz "
"that was used during provisioning", wpa_s->wps_freq);
params->freqs = os_zalloc(2 * sizeof(int));
if (params->freqs)
params->freqs[0] = wpa_s->wps_freq;
wpa_s->after_wps--;
}
if (params->freqs == NULL && wpa_s->known_wps_freq && wpa_s->wps_freq)
{
/* Optimize provisioning scan based on already known channel */
wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Scan only frequency %u MHz",
wpa_s->wps_freq);
params->freqs = os_zalloc(2 * sizeof(int));
if (params->freqs)
params->freqs[0] = wpa_s->wps_freq;
wpa_s->known_wps_freq = 0; /* only do this once */
}
#endif /* CONFIG_WPS */
}
#ifdef CONFIG_INTERWORKING
static void wpas_add_interworking_elements(struct wpa_supplicant *wpa_s,
struct wpabuf *buf)
{
if (wpa_s->conf->interworking == 0)
return;
wpabuf_put_u8(buf, WLAN_EID_EXT_CAPAB);
wpabuf_put_u8(buf, 4);
wpabuf_put_u8(buf, 0x00);
wpabuf_put_u8(buf, 0x00);
wpabuf_put_u8(buf, 0x00);
wpabuf_put_u8(buf, 0x80); /* Bit 31 - Interworking */
wpabuf_put_u8(buf, WLAN_EID_INTERWORKING);
wpabuf_put_u8(buf, is_zero_ether_addr(wpa_s->conf->hessid) ? 1 :
1 + ETH_ALEN);
wpabuf_put_u8(buf, wpa_s->conf->access_network_type);
/* No Venue Info */
if (!is_zero_ether_addr(wpa_s->conf->hessid))
wpabuf_put_data(buf, wpa_s->conf->hessid, ETH_ALEN);
}
#endif /* CONFIG_INTERWORKING */
static struct wpabuf * wpa_supplicant_extra_ies(struct wpa_supplicant *wpa_s)
{
struct wpabuf *extra_ie = NULL;
#ifdef CONFIG_WPS
int wps = 0;
enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
#endif /* CONFIG_WPS */
#ifdef CONFIG_INTERWORKING
if (wpa_s->conf->interworking &&
wpabuf_resize(&extra_ie, 100) == 0)
wpas_add_interworking_elements(wpa_s, extra_ie);
#endif /* CONFIG_INTERWORKING */
#ifdef CONFIG_WPS
wps = wpas_wps_in_use(wpa_s, &req_type);
if (wps) {
struct wpabuf *wps_ie;
wps_ie = wps_build_probe_req_ie(wps == 2 ? DEV_PW_PUSHBUTTON :
DEV_PW_DEFAULT,
&wpa_s->wps->dev,
wpa_s->wps->uuid, req_type,
0, NULL);
if (wps_ie) {
if (wpabuf_resize(&extra_ie, wpabuf_len(wps_ie)) == 0)
wpabuf_put_buf(extra_ie, wps_ie);
wpabuf_free(wps_ie);
}
}
#ifdef CONFIG_P2P
if (wps) {
size_t ielen = p2p_scan_ie_buf_len(wpa_s->global->p2p);
if (wpabuf_resize(&extra_ie, ielen) == 0)
wpas_p2p_scan_ie(wpa_s, extra_ie);
}
#endif /* CONFIG_P2P */
#endif /* CONFIG_WPS */
#ifdef CONFIG_HS20
if (wpa_s->conf->hs20 && wpabuf_resize(&extra_ie, 7) == 0)
wpas_hs20_add_indication(extra_ie);
#endif /* CONFIG_HS20 */
return extra_ie;
}
#ifdef CONFIG_P2P
/*
* Check whether there are any enabled networks or credentials that could be
* used for a non-P2P connection.
*/
static int non_p2p_network_enabled(struct wpa_supplicant *wpa_s)
{
struct wpa_ssid *ssid;
for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
if (wpas_network_disabled(wpa_s, ssid))
continue;
if (!ssid->p2p_group)
return 1;
}
if (wpa_s->conf->cred && wpa_s->conf->interworking &&
wpa_s->conf->auto_interworking)
return 1;
return 0;
}
#endif /* CONFIG_P2P */
static struct hostapd_hw_modes * get_mode(struct hostapd_hw_modes *modes,
u16 num_modes,
enum hostapd_hw_mode mode)
{
u16 i;
for (i = 0; i < num_modes; i++) {
if (modes[i].mode == mode)
return &modes[i];
}
return NULL;
}
static void wpa_setband_scan_freqs_list(struct wpa_supplicant *wpa_s,
enum hostapd_hw_mode band,
struct wpa_driver_scan_params *params)
{
/* Include only supported channels for the specified band */
struct hostapd_hw_modes *mode;
int count, i;
mode = get_mode(wpa_s->hw.modes, wpa_s->hw.num_modes, band);
if (mode == NULL) {
/* No channels supported in this band - use empty list */
params->freqs = os_zalloc(sizeof(int));
return;
}
params->freqs = os_zalloc((mode->num_channels + 1) * sizeof(int));
if (params->freqs == NULL)
return;
for (count = 0, i = 0; i < mode->num_channels; i++) {
if (mode->channels[i].flag & HOSTAPD_CHAN_DISABLED)
continue;
params->freqs[count++] = mode->channels[i].freq;
}
}
static void wpa_setband_scan_freqs(struct wpa_supplicant *wpa_s,
struct wpa_driver_scan_params *params)
{
if (wpa_s->hw.modes == NULL)
return; /* unknown what channels the driver supports */
if (params->freqs)
return; /* already using a limited channel set */
if (wpa_s->setband == WPA_SETBAND_5G)
wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211A,
params);
else if (wpa_s->setband == WPA_SETBAND_2G)
wpa_setband_scan_freqs_list(wpa_s, HOSTAPD_MODE_IEEE80211G,
params);
}
static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
{
struct wpa_supplicant *wpa_s = eloop_ctx;
struct wpa_ssid *ssid;
int ret;
struct wpabuf *extra_ie = NULL;
struct wpa_driver_scan_params params;
struct wpa_driver_scan_params *scan_params;
size_t max_ssids;
enum wpa_states prev_state;
if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
wpas_p2p_continue_after_scan(wpa_s);
return;
}
if (wpa_s->disconnected && wpa_s->scan_req == NORMAL_SCAN_REQ) {
wpa_dbg(wpa_s, MSG_DEBUG, "Disconnected - do not scan");
wpa_supplicant_set_state(wpa_s, WPA_DISCONNECTED);
wpas_p2p_continue_after_scan(wpa_s);
return;
}
if (wpa_s->scanning) {
/*
* If we are already in scanning state, we shall reschedule the
* the incoming scan request.
*/
wpa_dbg(wpa_s, MSG_DEBUG, "Already scanning - Reschedule the incoming scan req");
wpa_supplicant_req_scan(wpa_s, 1, 0);
return;
}
if (!wpa_supplicant_enabled_networks(wpa_s) &&
wpa_s->scan_req == NORMAL_SCAN_REQ) {
wpa_dbg(wpa_s, MSG_DEBUG, "No enabled networks - do not scan");
wpa_supplicant_set_state(wpa_s, WPA_INACTIVE);
wpas_p2p_continue_after_scan(wpa_s);
return;
}
if (wpa_s->conf->ap_scan != 0 &&
(wpa_s->drv_flags & WPA_DRIVER_FLAGS_WIRED)) {
wpa_dbg(wpa_s, MSG_DEBUG, "Using wired authentication - "
"overriding ap_scan configuration");
wpa_s->conf->ap_scan = 0;
wpas_notify_ap_scan_changed(wpa_s);
}
if (wpa_s->conf->ap_scan == 0) {
wpa_supplicant_gen_assoc_event(wpa_s);
return;
}
#ifdef CONFIG_P2P
if (wpas_p2p_in_progress(wpa_s) || wpas_wpa_is_in_progress(wpa_s, 0)) {
if (wpa_s->sta_scan_pending &&
wpas_p2p_in_progress(wpa_s) == 2 &&
wpa_s->global->p2p_cb_on_scan_complete) {
wpa_dbg(wpa_s, MSG_DEBUG, "Process pending station "
"mode scan during P2P search");
} else {
wpa_dbg(wpa_s, MSG_DEBUG, "Delay station mode scan "
"while P2P operation is in progress");
wpa_s->sta_scan_pending = 1;
wpa_supplicant_req_scan(wpa_s, 5, 0);
return;
}
}
#endif /* CONFIG_P2P */
#ifdef CONFIG_GAS
if (gas_query_in_progress(wpa_s->gas)) {
wpa_dbg(wpa_s, MSG_DEBUG, "Delay scan while GAS query is in progress");
wpa_supplicant_req_scan(wpa_s, 1, 0);
return;
}
#endif /* CONFIG_GAS */
if (wpa_s->conf->ap_scan == 2)
max_ssids = 1;
else {
max_ssids = wpa_s->max_scan_ssids;
if (max_ssids > WPAS_MAX_SCAN_SSIDS)
max_ssids = WPAS_MAX_SCAN_SSIDS;
}
wpa_s->last_scan_req = wpa_s->scan_req;
wpa_s->scan_req = NORMAL_SCAN_REQ;
os_memset(&params, 0, sizeof(params));
prev_state = wpa_s->wpa_state;
if (wpa_s->wpa_state == WPA_DISCONNECTED ||
wpa_s->wpa_state == WPA_INACTIVE)
wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
/*
* If autoscan has set its own scanning parameters
*/
if (wpa_s->autoscan_params != NULL) {
scan_params = wpa_s->autoscan_params;
goto scan;
}
if (wpa_s->last_scan_req != MANUAL_SCAN_REQ &&
wpa_s->connect_without_scan) {
for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
if (ssid == wpa_s->connect_without_scan)
break;
}
wpa_s->connect_without_scan = NULL;
if (ssid) {
wpa_printf(MSG_DEBUG, "Start a pre-selected network "
"without scan step");
wpa_supplicant_associate(wpa_s, NULL, ssid);
return;
}
}
#ifdef CONFIG_P2P
if ((wpa_s->p2p_in_provisioning || wpa_s->show_group_started) &&
wpa_s->go_params) {
wpa_printf(MSG_DEBUG, "P2P: Use specific SSID for scan during P2P group formation (p2p_in_provisioning=%d show_group_started=%d)",
wpa_s->p2p_in_provisioning,
wpa_s->show_group_started);
params.ssids[0].ssid = wpa_s->go_params->ssid;
params.ssids[0].ssid_len = wpa_s->go_params->ssid_len;
params.num_ssids = 1;
goto ssid_list_set;
}
#endif /* CONFIG_P2P */
/* Find the starting point from which to continue scanning */
ssid = wpa_s->conf->ssid;
if (wpa_s->prev_scan_ssid != WILDCARD_SSID_SCAN) {
while (ssid) {
if (ssid == wpa_s->prev_scan_ssid) {
ssid = ssid->next;
break;
}
ssid = ssid->next;
}
}
if (wpa_s->last_scan_req != MANUAL_SCAN_REQ &&
wpa_s->conf->ap_scan == 2) {
wpa_s->connect_without_scan = NULL;
wpa_s->prev_scan_wildcard = 0;
wpa_supplicant_assoc_try(wpa_s, ssid);
return;
} else if (wpa_s->conf->ap_scan == 2) {
/*
* User-initiated scan request in ap_scan == 2; scan with
* wildcard SSID.
*/
ssid = NULL;
} else {
struct wpa_ssid *start = ssid, *tssid;
int freqs_set = 0;
if (ssid == NULL && max_ssids > 1)
ssid = wpa_s->conf->ssid;
while (ssid) {
if (!wpas_network_disabled(wpa_s, ssid) &&
ssid->scan_ssid) {
wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
ssid->ssid, ssid->ssid_len);
params.ssids[params.num_ssids].ssid =
ssid->ssid;
params.ssids[params.num_ssids].ssid_len =
ssid->ssid_len;
params.num_ssids++;
if (params.num_ssids + 1 >= max_ssids)
break;
}
ssid = ssid->next;
if (ssid == start)
break;
if (ssid == NULL && max_ssids > 1 &&
start != wpa_s->conf->ssid)
ssid = wpa_s->conf->ssid;
}
for (tssid = wpa_s->conf->ssid; tssid; tssid = tssid->next) {
if (wpas_network_disabled(wpa_s, tssid))
continue;
if ((params.freqs || !freqs_set) && tssid->scan_freq) {
int_array_concat(&params.freqs,
tssid->scan_freq);
} else {
os_free(params.freqs);
params.freqs = NULL;
}
freqs_set = 1;
}
int_array_sort_unique(params.freqs);
}
if (ssid && max_ssids == 1) {
/*
* If the driver is limited to 1 SSID at a time interleave
* wildcard SSID scans with specific SSID scans to avoid
* waiting a long time for a wildcard scan.
*/
if (!wpa_s->prev_scan_wildcard) {
params.ssids[0].ssid = NULL;
params.ssids[0].ssid_len = 0;
wpa_s->prev_scan_wildcard = 1;
wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for "
"wildcard SSID (Interleave with specific)");
} else {
wpa_s->prev_scan_ssid = ssid;
wpa_s->prev_scan_wildcard = 0;
wpa_dbg(wpa_s, MSG_DEBUG,
"Starting AP scan for specific SSID: %s",
wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
}
} else if (ssid) {
/* max_ssids > 1 */
wpa_s->prev_scan_ssid = ssid;
wpa_dbg(wpa_s, MSG_DEBUG, "Include wildcard SSID in "
"the scan request");
params.num_ssids++;
} else {
wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
params.num_ssids++;
wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
"SSID");
}
#ifdef CONFIG_P2P
ssid_list_set:
#endif /* CONFIG_P2P */
wpa_supplicant_optimize_freqs(wpa_s, &params);
extra_ie = wpa_supplicant_extra_ies(wpa_s);
if (params.freqs == NULL && wpa_s->next_scan_freqs) {
wpa_dbg(wpa_s, MSG_DEBUG, "Optimize scan based on previously "
"generated frequency list");
params.freqs = wpa_s->next_scan_freqs;
} else
os_free(wpa_s->next_scan_freqs);
wpa_s->next_scan_freqs = NULL;
wpa_setband_scan_freqs(wpa_s, &params);
/* See if user specified frequencies. If so, scan only those. */
if (wpa_s->conf->freq_list && !params.freqs) {
wpa_dbg(wpa_s, MSG_DEBUG,
"Optimize scan based on conf->freq_list");
int_array_concat(&params.freqs, wpa_s->conf->freq_list);
}
/* Use current associated channel? */
if (wpa_s->conf->scan_cur_freq && !params.freqs) {
unsigned int num = wpa_s->num_multichan_concurrent;
params.freqs = os_calloc(num + 1, sizeof(int));
if (params.freqs) {
num = get_shared_radio_freqs(wpa_s, params.freqs, num);
if (num > 0) {
wpa_dbg(wpa_s, MSG_DEBUG, "Scan only the "
"current operating channels since "
"scan_cur_freq is enabled");
} else {
os_free(params.freqs);
params.freqs = NULL;
}
}
}
params.filter_ssids = wpa_supplicant_build_filter_ssids(
wpa_s->conf, &params.num_filter_ssids);
if (extra_ie) {
params.extra_ies = wpabuf_head(extra_ie);
params.extra_ies_len = wpabuf_len(extra_ie);
}
#ifdef CONFIG_P2P
if (wpa_s->p2p_in_provisioning ||
(wpa_s->show_group_started && wpa_s->go_params)) {
/*
* The interface may not yet be in P2P mode, so we have to
* explicitly request P2P probe to disable CCK rates.
*/
params.p2p_probe = 1;
}
#endif /* CONFIG_P2P */
scan_params = &params;
scan:
#ifdef CONFIG_P2P
/*
* If the driver does not support multi-channel concurrency and a
* virtual interface that shares the same radio with the wpa_s interface
* is operating there may not be need to scan other channels apart from
* the current operating channel on the other virtual interface. Filter
* out other channels in case we are trying to find a connection for a
* station interface when we are not configured to prefer station
* connection and a concurrent operation is already in process.
*/
if (wpa_s->scan_for_connection &&
wpa_s->last_scan_req == NORMAL_SCAN_REQ &&
!scan_params->freqs && !params.freqs &&
wpas_is_p2p_prioritized(wpa_s) &&
wpa_s->p2p_group_interface == NOT_P2P_GROUP_INTERFACE &&
non_p2p_network_enabled(wpa_s)) {
unsigned int num = wpa_s->num_multichan_concurrent;
params.freqs = os_calloc(num + 1, sizeof(int));
if (params.freqs) {
num = get_shared_radio_freqs(wpa_s, params.freqs, num);
if (num > 0 && num == wpa_s->num_multichan_concurrent) {
wpa_dbg(wpa_s, MSG_DEBUG, "Scan only the current operating channels since all channels are already used");
} else {
os_free(params.freqs);
params.freqs = NULL;
}
}
}
#endif /* CONFIG_P2P */
ret = wpa_supplicant_trigger_scan(wpa_s, scan_params);
wpabuf_free(extra_ie);
os_free(params.freqs);
os_free(params.filter_ssids);
if (ret) {
wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate AP scan");
if (prev_state != wpa_s->wpa_state)
wpa_supplicant_set_state(wpa_s, prev_state);
/* Restore scan_req since we will try to scan again */
wpa_s->scan_req = wpa_s->last_scan_req;
wpa_supplicant_req_scan(wpa_s, 1, 0);
} else {
wpa_s->scan_for_connection = 0;
}
}
void wpa_supplicant_update_scan_int(struct wpa_supplicant *wpa_s, int sec)
{
struct os_reltime remaining, new_int;
int cancelled;
cancelled = eloop_cancel_timeout_one(wpa_supplicant_scan, wpa_s, NULL,
&remaining);
new_int.sec = sec;
new_int.usec = 0;
if (cancelled && os_reltime_before(&remaining, &new_int)) {
new_int.sec = remaining.sec;
new_int.usec = remaining.usec;
}
if (cancelled) {
eloop_register_timeout(new_int.sec, new_int.usec,
wpa_supplicant_scan, wpa_s, NULL);
}
wpa_s->scan_interval = sec;
}
/**
* wpa_supplicant_req_scan - Schedule a scan for neighboring access points
* @wpa_s: Pointer to wpa_supplicant data
* @sec: Number of seconds after which to scan
* @usec: Number of microseconds after which to scan
*
* This function is used to schedule a scan for neighboring access points after
* the specified time.
*/
void wpa_supplicant_req_scan(struct wpa_supplicant *wpa_s, int sec, int usec)
{
if (eloop_deplete_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL))
{
wpa_dbg(wpa_s, MSG_DEBUG, "Rescheduling scan request: %d sec %d usec",
sec, usec);
return;
}
wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d sec %d usec",
sec, usec);
eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
eloop_register_timeout(sec, usec, wpa_supplicant_scan, wpa_s, NULL);
}
/**
* wpa_supplicant_delayed_sched_scan - Request a delayed scheduled scan
* @wpa_s: Pointer to wpa_supplicant data
* @sec: Number of seconds after which to scan
* @usec: Number of microseconds after which to scan
* Returns: 0 on success or -1 otherwise
*
* This function is used to schedule periodic scans for neighboring
* access points after the specified time.
*/
int wpa_supplicant_delayed_sched_scan(struct wpa_supplicant *wpa_s,
int sec, int usec)
{
if (!wpa_s->sched_scan_supported)
return -1;
eloop_register_timeout(sec, usec,
wpa_supplicant_delayed_sched_scan_timeout,
wpa_s, NULL);
return 0;
}
/**
* wpa_supplicant_req_sched_scan - Start a periodic scheduled scan
* @wpa_s: Pointer to wpa_supplicant data
* Returns: 0 is sched_scan was started or -1 otherwise
*
* This function is used to schedule periodic scans for neighboring
* access points repeating the scan continuously.
*/
int wpa_supplicant_req_sched_scan(struct wpa_supplicant *wpa_s)
{
struct wpa_driver_scan_params params;
struct wpa_driver_scan_params *scan_params;
enum wpa_states prev_state;
struct wpa_ssid *ssid = NULL;
struct wpabuf *extra_ie = NULL;
int ret;
unsigned int max_sched_scan_ssids;
int wildcard = 0;
int need_ssids;
if (!wpa_s->sched_scan_supported)
return -1;
if (wpa_s->max_sched_scan_ssids > WPAS_MAX_SCAN_SSIDS)
max_sched_scan_ssids = WPAS_MAX_SCAN_SSIDS;
else
max_sched_scan_ssids = wpa_s->max_sched_scan_ssids;
if (max_sched_scan_ssids < 1 || wpa_s->conf->disable_scan_offload)
return -1;
if (wpa_s->sched_scanning) {
wpa_dbg(wpa_s, MSG_DEBUG, "Already sched scanning");
return 0;
}
need_ssids = 0;
for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
if (!wpas_network_disabled(wpa_s, ssid) && !ssid->scan_ssid) {
/* Use wildcard SSID to find this network */
wildcard = 1;
} else if (!wpas_network_disabled(wpa_s, ssid) &&
ssid->ssid_len)
need_ssids++;
#ifdef CONFIG_WPS
if (!wpas_network_disabled(wpa_s, ssid) &&
ssid->key_mgmt == WPA_KEY_MGMT_WPS) {
/*
* Normal scan is more reliable and faster for WPS
* operations and since these are for short periods of
* time, the benefit of trying to use sched_scan would
* be limited.
*/
wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
"sched_scan for WPS");
return -1;
}
#endif /* CONFIG_WPS */
}
if (wildcard)
need_ssids++;
if (wpa_s->normal_scans < 3 &&
(need_ssids <= wpa_s->max_scan_ssids ||
wpa_s->max_scan_ssids >= (int) max_sched_scan_ssids)) {
/*
* When normal scan can speed up operations, use that for the
* first operations before starting the sched_scan to allow
* user space sleep more. We do this only if the normal scan
* has functionality that is suitable for this or if the
* sched_scan does not have better support for multiple SSIDs.
*/
wpa_dbg(wpa_s, MSG_DEBUG, "Use normal scan instead of "
"sched_scan for initial scans (normal_scans=%d)",
wpa_s->normal_scans);
return -1;
}
os_memset(&params, 0, sizeof(params));
/* If we can't allocate space for the filters, we just don't filter */
params.filter_ssids = os_zalloc(wpa_s->max_match_sets *
sizeof(struct wpa_driver_scan_filter));
prev_state = wpa_s->wpa_state;
if (wpa_s->wpa_state == WPA_DISCONNECTED ||
wpa_s->wpa_state == WPA_INACTIVE)
wpa_supplicant_set_state(wpa_s, WPA_SCANNING);
if (wpa_s->autoscan_params != NULL) {
scan_params = wpa_s->autoscan_params;
goto scan;
}
/* Find the starting point from which to continue scanning */
ssid = wpa_s->conf->ssid;
if (wpa_s->prev_sched_ssid) {
while (ssid) {
if (ssid == wpa_s->prev_sched_ssid) {
ssid = ssid->next;
break;
}
ssid = ssid->next;
}
}
if (!ssid || !wpa_s->prev_sched_ssid) {
wpa_dbg(wpa_s, MSG_DEBUG, "Beginning of SSID list");
if (wpa_s->conf->sched_scan_interval)
wpa_s->sched_scan_interval =
wpa_s->conf->sched_scan_interval;
if (wpa_s->sched_scan_interval == 0)
wpa_s->sched_scan_interval = 10;
wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
wpa_s->first_sched_scan = 1;
ssid = wpa_s->conf->ssid;
wpa_s->prev_sched_ssid = ssid;
}
if (wildcard) {
wpa_dbg(wpa_s, MSG_DEBUG, "Add wildcard SSID to sched_scan");
params.num_ssids++;
}
while (ssid) {
if (wpas_network_disabled(wpa_s, ssid))
goto next;
if (params.num_filter_ssids < wpa_s->max_match_sets &&
params.filter_ssids && ssid->ssid && ssid->ssid_len) {
wpa_dbg(wpa_s, MSG_DEBUG, "add to filter ssid: %s",
wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
os_memcpy(params.filter_ssids[params.num_filter_ssids].ssid,
ssid->ssid, ssid->ssid_len);
params.filter_ssids[params.num_filter_ssids].ssid_len =
ssid->ssid_len;
params.num_filter_ssids++;
} else if (params.filter_ssids && ssid->ssid && ssid->ssid_len)
{
wpa_dbg(wpa_s, MSG_DEBUG, "Not enough room for SSID "
"filter for sched_scan - drop filter");
os_free(params.filter_ssids);
params.filter_ssids = NULL;
params.num_filter_ssids = 0;
}
if (ssid->scan_ssid && ssid->ssid && ssid->ssid_len) {
if (params.num_ssids == max_sched_scan_ssids)
break; /* only room for broadcast SSID */
wpa_dbg(wpa_s, MSG_DEBUG,
"add to active scan ssid: %s",
wpa_ssid_txt(ssid->ssid, ssid->ssid_len));
params.ssids[params.num_ssids].ssid =
ssid->ssid;
params.ssids[params.num_ssids].ssid_len =
ssid->ssid_len;
params.num_ssids++;
if (params.num_ssids >= max_sched_scan_ssids) {
wpa_s->prev_sched_ssid = ssid;
do {
ssid = ssid->next;
} while (ssid &&
(wpas_network_disabled(wpa_s, ssid) ||
!ssid->scan_ssid));
break;
}
}
next:
wpa_s->prev_sched_ssid = ssid;
ssid = ssid->next;
}
if (params.num_filter_ssids == 0) {
os_free(params.filter_ssids);
params.filter_ssids = NULL;
}
extra_ie = wpa_supplicant_extra_ies(wpa_s);
if (extra_ie) {
params.extra_ies = wpabuf_head(extra_ie);
params.extra_ies_len = wpabuf_len(extra_ie);
}
scan_params = &params;
scan:
if (ssid || !wpa_s->first_sched_scan) {
wpa_dbg(wpa_s, MSG_DEBUG,
"Starting sched scan: interval %d timeout %d",
wpa_s->sched_scan_interval, wpa_s->sched_scan_timeout);
} else {
wpa_dbg(wpa_s, MSG_DEBUG,
"Starting sched scan: interval %d (no timeout)",
wpa_s->sched_scan_interval);
}
wpa_setband_scan_freqs(wpa_s, scan_params);
ret = wpa_supplicant_start_sched_scan(wpa_s, scan_params,
wpa_s->sched_scan_interval);
wpabuf_free(extra_ie);
os_free(params.filter_ssids);
if (ret) {
wpa_msg(wpa_s, MSG_WARNING, "Failed to initiate sched scan");
if (prev_state != wpa_s->wpa_state)
wpa_supplicant_set_state(wpa_s, prev_state);
return ret;
}
/* If we have more SSIDs to scan, add a timeout so we scan them too */
if (ssid || !wpa_s->first_sched_scan) {
wpa_s->sched_scan_timed_out = 0;
eloop_register_timeout(wpa_s->sched_scan_timeout, 0,
wpa_supplicant_sched_scan_timeout,
wpa_s, NULL);
wpa_s->first_sched_scan = 0;
wpa_s->sched_scan_timeout /= 2;
wpa_s->sched_scan_interval *= 2;
if (wpa_s->sched_scan_timeout < wpa_s->sched_scan_interval) {
wpa_s->sched_scan_interval = 10;
wpa_s->sched_scan_timeout = max_sched_scan_ssids * 2;
}
}
/* If there is no more ssids, start next time from the beginning */
if (!ssid)
wpa_s->prev_sched_ssid = NULL;
return 0;
}
/**
* wpa_supplicant_cancel_scan - Cancel a scheduled scan request
* @wpa_s: Pointer to wpa_supplicant data
*
* This function is used to cancel a scan request scheduled with
* wpa_supplicant_req_scan().
*/
void wpa_supplicant_cancel_scan(struct wpa_supplicant *wpa_s)
{
wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling scan request");
eloop_cancel_timeout(wpa_supplicant_scan, wpa_s, NULL);
wpas_p2p_continue_after_scan(wpa_s);
}
/**
* wpa_supplicant_cancel_delayed_sched_scan - Stop a delayed scheduled scan
* @wpa_s: Pointer to wpa_supplicant data
*
* This function is used to stop a delayed scheduled scan.
*/
void wpa_supplicant_cancel_delayed_sched_scan(struct wpa_supplicant *wpa_s)
{
if (!wpa_s->sched_scan_supported)
return;
wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling delayed sched scan");
eloop_cancel_timeout(wpa_supplicant_delayed_sched_scan_timeout,
wpa_s, NULL);
}
/**
* wpa_supplicant_cancel_sched_scan - Stop running scheduled scans
* @wpa_s: Pointer to wpa_supplicant data
*
* This function is used to stop a periodic scheduled scan.
*/
void wpa_supplicant_cancel_sched_scan(struct wpa_supplicant *wpa_s)
{
if (!wpa_s->sched_scanning)
return;
wpa_dbg(wpa_s, MSG_DEBUG, "Cancelling sched scan");
eloop_cancel_timeout(wpa_supplicant_sched_scan_timeout, wpa_s, NULL);
wpa_supplicant_stop_sched_scan(wpa_s);
}
/**
* wpa_supplicant_notify_scanning - Indicate possible scan state change
* @wpa_s: Pointer to wpa_supplicant data
* @scanning: Whether scanning is currently in progress
*
* This function is to generate scanning notifycations. It is called whenever
* there may have been a change in scanning (scan started, completed, stopped).
* wpas_notify_scanning() is called whenever the scanning state changed from the
* previously notified state.
*/
void wpa_supplicant_notify_scanning(struct wpa_supplicant *wpa_s,
int scanning)
{
if (wpa_s->scanning != scanning) {
wpa_s->scanning = scanning;
wpas_notify_scanning(wpa_s);
}
}
static int wpa_scan_get_max_rate(const struct wpa_scan_res *res)
{
int rate = 0;
const u8 *ie;
int i;
ie = wpa_scan_get_ie(res, 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_scan_get_ie(res, 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_scan_get_ie - Fetch a specified information element from a scan result
* @res: Scan result 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 scan
* result.
*/
const u8 * wpa_scan_get_ie(const struct wpa_scan_res *res, u8 ie)
{
const u8 *end, *pos;
pos = (const u8 *) (res + 1);
end = pos + res->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_scan_get_vendor_ie - Fetch vendor information element from a scan result
* @res: Scan result 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 scan
* result.
*/
const u8 * wpa_scan_get_vendor_ie(const struct wpa_scan_res *res,
u32 vendor_type)
{
const u8 *end, *pos;
pos = (const u8 *) (res + 1);
end = pos + res->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_scan_get_vendor_ie_beacon - Fetch vendor information from a scan result
* @res: Scan result 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 scan
* result.
*
* This function is like wpa_scan_get_vendor_ie(), but uses IE buffer only
* from Beacon frames instead of either Beacon or Probe Response frames.
*/
const u8 * wpa_scan_get_vendor_ie_beacon(const struct wpa_scan_res *res,
u32 vendor_type)
{
const u8 *end, *pos;
if (res->beacon_ie_len == 0)
return NULL;
pos = (const u8 *) (res + 1);
pos += res->ie_len;
end = pos + res->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_scan_get_vendor_ie_multi - Fetch vendor IE data from a scan result
* @res: Scan result 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 scan result. The caller is responsible
* for freeing the returned buffer.
*/
struct wpabuf * wpa_scan_get_vendor_ie_multi(const struct wpa_scan_res *res,
u32 vendor_type)
{
struct wpabuf *buf;
const u8 *end, *pos;
buf = wpabuf_alloc(res->ie_len);
if (buf == NULL)
return NULL;
pos = (const u8 *) (res + 1);
end = pos + res->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;
}
/*
* Channels with a great SNR can operate at full rate. What is a great SNR?
* This doc https://supportforums.cisco.com/docs/DOC-12954 says, "the general
* rule of thumb is that any SNR above 20 is good." This one
* http://www.cisco.com/en/US/tech/tk722/tk809/technologies_q_and_a_item09186a00805e9a96.shtml#qa23
* recommends 25 as a minimum SNR for 54 Mbps data rate. 30 is chosen here as a
* conservative value.
*/
#define GREAT_SNR 30
/* Compare function for sorting scan results. Return >0 if @b is considered
* better. */
static int wpa_scan_result_compar(const void *a, const void *b)
{
#define IS_5GHZ(n) (n > 4000)
#define MIN(a,b) a < b ? a : b
struct wpa_scan_res **_wa = (void *) a;
struct wpa_scan_res **_wb = (void *) b;
struct wpa_scan_res *wa = *_wa;
struct wpa_scan_res *wb = *_wb;
int wpa_a, wpa_b, maxrate_a, maxrate_b;
int snr_a, snr_b;
/* WPA/WPA2 support preferred */
wpa_a = wpa_scan_get_vendor_ie(wa, WPA_IE_VENDOR_TYPE) != NULL ||
wpa_scan_get_ie(wa, WLAN_EID_RSN) != NULL;
wpa_b = wpa_scan_get_vendor_ie(wb, WPA_IE_VENDOR_TYPE) != NULL ||
wpa_scan_get_ie(wb, WLAN_EID_RSN) != NULL;
if (wpa_b && !wpa_a)
return 1;
if (!wpa_b && wpa_a)
return -1;
/* privacy support preferred */
if ((wa->caps & IEEE80211_CAP_PRIVACY) == 0 &&
(wb->caps & IEEE80211_CAP_PRIVACY))
return 1;
if ((wa->caps & IEEE80211_CAP_PRIVACY) &&
(wb->caps & IEEE80211_CAP_PRIVACY) == 0)
return -1;
if ((wa->flags & wb->flags & WPA_SCAN_LEVEL_DBM) &&
!((wa->flags | wb->flags) & WPA_SCAN_NOISE_INVALID)) {
snr_a = MIN(wa->level - wa->noise, GREAT_SNR);
snr_b = MIN(wb->level - wb->noise, GREAT_SNR);
} else {
/* Not suitable information to calculate SNR, so use level */
snr_a = wa->level;
snr_b = wb->level;
}
/* best/max rate preferred if SNR close enough */
if ((snr_a && snr_b && abs(snr_b - snr_a) < 5) ||
(wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
maxrate_a = wpa_scan_get_max_rate(wa);
maxrate_b = wpa_scan_get_max_rate(wb);
if (maxrate_a != maxrate_b)
return maxrate_b - maxrate_a;
if (IS_5GHZ(wa->freq) ^ IS_5GHZ(wb->freq))
return IS_5GHZ(wa->freq) ? -1 : 1;
}
/* use freq for channel preference */
/* all things being equal, use SNR; if SNRs are
* identical, use quality values since some drivers may only report
* that value and leave the signal level zero */
if (snr_b == snr_a)
return wb->qual - wa->qual;
return snr_b - snr_a;
#undef MIN
#undef IS_5GHZ
}
#ifdef CONFIG_WPS
/* Compare function for sorting scan results when searching a WPS AP for
* provisioning. Return >0 if @b is considered better. */
static int wpa_scan_result_wps_compar(const void *a, const void *b)
{
struct wpa_scan_res **_wa = (void *) a;
struct wpa_scan_res **_wb = (void *) b;
struct wpa_scan_res *wa = *_wa;
struct wpa_scan_res *wb = *_wb;
int uses_wps_a, uses_wps_b;
struct wpabuf *wps_a, *wps_b;
int res;
/* Optimization - check WPS IE existence before allocated memory and
* doing full reassembly. */
uses_wps_a = wpa_scan_get_vendor_ie(wa, WPS_IE_VENDOR_TYPE) != NULL;
uses_wps_b = wpa_scan_get_vendor_ie(wb, WPS_IE_VENDOR_TYPE) != NULL;
if (uses_wps_a && !uses_wps_b)
return -1;
if (!uses_wps_a && uses_wps_b)
return 1;
if (uses_wps_a && uses_wps_b) {
wps_a = wpa_scan_get_vendor_ie_multi(wa, WPS_IE_VENDOR_TYPE);
wps_b = wpa_scan_get_vendor_ie_multi(wb, WPS_IE_VENDOR_TYPE);
res = wps_ap_priority_compar(wps_a, wps_b);
wpabuf_free(wps_a);
wpabuf_free(wps_b);
if (res)
return res;
}
/*
* Do not use current AP security policy as a sorting criteria during
* WPS provisioning step since the AP may get reconfigured at the
* completion of provisioning.
*/
/* all things being equal, use signal level; if signal levels are
* identical, use quality values since some drivers may only report
* that value and leave the signal level zero */
if (wb->level == wa->level)
return wb->qual - wa->qual;
return wb->level - wa->level;
}
#endif /* CONFIG_WPS */
static void dump_scan_res(struct wpa_scan_results *scan_res)
{
#ifndef CONFIG_NO_STDOUT_DEBUG
size_t i;
if (scan_res->res == NULL || scan_res->num == 0)
return;
wpa_printf(MSG_EXCESSIVE, "Sorted scan results");
for (i = 0; i < scan_res->num; i++) {
struct wpa_scan_res *r = scan_res->res[i];
u8 *pos;
if ((r->flags & (WPA_SCAN_LEVEL_DBM | WPA_SCAN_NOISE_INVALID))
== WPA_SCAN_LEVEL_DBM) {
int snr = r->level - r->noise;
wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
"noise=%d level=%d snr=%d%s flags=0x%x "
"age=%u",
MAC2STR(r->bssid), r->freq, r->qual,
r->noise, r->level, snr,
snr >= GREAT_SNR ? "*" : "", r->flags,
r->age);
} else {
wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
"noise=%d level=%d flags=0x%x age=%u",
MAC2STR(r->bssid), r->freq, r->qual,
r->noise, r->level, r->flags, r->age);
}
pos = (u8 *) (r + 1);
if (r->ie_len)
wpa_hexdump(MSG_EXCESSIVE, "IEs", pos, r->ie_len);
pos += r->ie_len;
if (r->beacon_ie_len)
wpa_hexdump(MSG_EXCESSIVE, "Beacon IEs",
pos, r->beacon_ie_len);
}
#endif /* CONFIG_NO_STDOUT_DEBUG */
}
/**
* wpa_supplicant_filter_bssid_match - Is the specified BSSID allowed
* @wpa_s: Pointer to wpa_supplicant data
* @bssid: BSSID to check
* Returns: 0 if the BSSID is filtered or 1 if not
*
* This function is used to filter out specific BSSIDs from scan reslts mainly
* for testing purposes (SET bssid_filter ctrl_iface command).
*/
int wpa_supplicant_filter_bssid_match(struct wpa_supplicant *wpa_s,
const u8 *bssid)
{
size_t i;
if (wpa_s->bssid_filter == NULL)
return 1;
for (i = 0; i < wpa_s->bssid_filter_count; i++) {
if (os_memcmp(wpa_s->bssid_filter + i * ETH_ALEN, bssid,
ETH_ALEN) == 0)
return 1;
}
return 0;
}
static void filter_scan_res(struct wpa_supplicant *wpa_s,
struct wpa_scan_results *res)
{
size_t i, j;
if (wpa_s->bssid_filter == NULL)
return;
for (i = 0, j = 0; i < res->num; i++) {
if (wpa_supplicant_filter_bssid_match(wpa_s,
res->res[i]->bssid)) {
res->res[j++] = res->res[i];
} else {
os_free(res->res[i]);
res->res[i] = NULL;
}
}
if (res->num != j) {
wpa_printf(MSG_DEBUG, "Filtered out %d scan results",
(int) (res->num - j));
res->num = j;
}
}
/**
* wpa_supplicant_get_scan_results - Get scan results
* @wpa_s: Pointer to wpa_supplicant data
* @info: Information about what was scanned or %NULL if not available
* @new_scan: Whether a new scan was performed
* Returns: Scan results, %NULL on failure
*
* This function request the current scan results from the driver and updates
* the local BSS list wpa_s->bss. The caller is responsible for freeing the
* results with wpa_scan_results_free().
*/
struct wpa_scan_results *
wpa_supplicant_get_scan_results(struct wpa_supplicant *wpa_s,
struct scan_info *info, int new_scan)
{
struct wpa_scan_results *scan_res;
size_t i;
int (*compar)(const void *, const void *) = wpa_scan_result_compar;
scan_res = wpa_drv_get_scan_results2(wpa_s);
if (scan_res == NULL) {
wpa_dbg(wpa_s, MSG_DEBUG, "Failed to get scan results");
return NULL;
}
if (scan_res->fetch_time.sec == 0) {
/*
* Make sure we have a valid timestamp if the driver wrapper
* does not set this.
*/
os_get_reltime(&scan_res->fetch_time);
}
filter_scan_res(wpa_s, scan_res);
#ifdef CONFIG_WPS
if (wpas_wps_in_progress(wpa_s)) {
wpa_dbg(wpa_s, MSG_DEBUG, "WPS: Order scan results with WPS "
"provisioning rules");
compar = wpa_scan_result_wps_compar;
}
#endif /* CONFIG_WPS */
qsort(scan_res->res, scan_res->num, sizeof(struct wpa_scan_res *),
compar);
dump_scan_res(scan_res);
wpa_bss_update_start(wpa_s);
for (i = 0; i < scan_res->num; i++)
wpa_bss_update_scan_res(wpa_s, scan_res->res[i],
&scan_res->fetch_time);
wpa_bss_update_end(wpa_s, info, new_scan);
return scan_res;
}
/**
* wpa_supplicant_update_scan_results - Update scan results from the driver
* @wpa_s: Pointer to wpa_supplicant data
* Returns: 0 on success, -1 on failure
*
* This function updates the BSS table within wpa_supplicant based on the
* currently available scan results from the driver without requesting a new
* scan. This is used in cases where the driver indicates an association
* (including roaming within ESS) and wpa_supplicant does not yet have the
* needed information to complete the connection (e.g., to perform validation
* steps in 4-way handshake).
*/
int wpa_supplicant_update_scan_results(struct wpa_supplicant *wpa_s)
{
struct wpa_scan_results *scan_res;
scan_res = wpa_supplicant_get_scan_results(wpa_s, NULL, 0);
if (scan_res == NULL)
return -1;
wpa_scan_results_free(scan_res);
return 0;
}
/**
* scan_only_handler - Reports scan results
*/
void scan_only_handler(struct wpa_supplicant *wpa_s,
struct wpa_scan_results *scan_res)
{
wpa_dbg(wpa_s, MSG_DEBUG, "Scan-only results received");
wpa_msg_ctrl(wpa_s, MSG_INFO, WPA_EVENT_SCAN_RESULTS);
wpas_notify_scan_results(wpa_s);
wpas_notify_scan_done(wpa_s, 1);
}
int wpas_scan_scheduled(struct wpa_supplicant *wpa_s)
{
return eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL);
}