hostap/wpa_supplicant/scan.c

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/*
* WPA Supplicant - Scanning
* Copyright (c) 2003-2014, 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 "scan.h"
#include "mesh.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;
if (wpa_s->p2p_mgmt)
return 0; /* no normal network profiles on p2p_mgmt interface */
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 void wpas_trigger_scan_cb(struct wpa_radio_work *work, int deinit)
{
struct wpa_supplicant *wpa_s = work->wpa_s;
struct wpa_driver_scan_params *params = work->ctx;
int ret;
if (deinit) {
if (!work->started) {
wpa_scan_free_params(params);
return;
}
wpa_supplicant_notify_scanning(wpa_s, 0);
wpas_notify_scan_done(wpa_s, 0);
wpa_s->scan_work = NULL;
return;
}
Add support for using random local MAC address This adds experimental support for wpa_supplicant to assign random local MAC addresses for both pre-association cases (scan, GAS/ANQP) and for connections. MAC address policy for each part can be controlled separately and the connection part can be set per network block. This requires support from the driver to allow local MAC address to be changed if random address policy is enabled. It should also be noted that number of drivers would not support concurrent operations (e.g., P2P and station association) with random addresses in use for one or both. This functionality can be controlled with the global configuration parameters mac_addr and preassoc_mac_addr which set the default MAC address policies for connections and pre-association operations (scan and GAS/ANQP while not connected). The global rand_addr_lifetime parameter can be used to set the lifetime of a random MAC address in seconds (default: 60 seconds). This is used to avoid unnecessarily frequent MAC address changes since those are likely to result in driver clearing most of its state. It should be noted that the random MAC address does not expire during an ESS connection, i.e., this lifetime is only for the case where the device is disconnected. The mac_addr parameter can also be set in the network blocks to define different behavior per network. For example, the global mac_addr=1 and preassoc_mac_addr=1 settings and mac_addr=0 in a home network profile would result in behavior where all scanning is performed using a random MAC address while connections to new networks (e.g., Interworking/Hotspot 2.0) would use random address and connections to the home network would use the permanent MAC address. Signed-off-by: Jouni Malinen <j@w1.fi>
2014-09-27 18:12:41 +02:00
if (wpas_update_random_addr_disassoc(wpa_s) < 0) {
wpa_msg(wpa_s, MSG_INFO,
"Failed to assign random MAC address for a scan");
radio_work_done(work);
return;
}
wpa_supplicant_notify_scanning(wpa_s, 1);
if (wpa_s->clear_driver_scan_cache) {
wpa_printf(MSG_DEBUG,
"Request driver to clear scan cache due to local BSS flush");
params->only_new_results = 1;
}
ret = wpa_drv_scan(wpa_s, params);
wpa_scan_free_params(params);
work->ctx = NULL;
if (ret) {
int retry = wpa_s->last_scan_req != MANUAL_SCAN_REQ;
if (wpa_s->disconnected)
retry = 0;
wpa_supplicant_notify_scanning(wpa_s, 0);
wpas_notify_scan_done(wpa_s, 0);
if (wpa_s->wpa_state == WPA_SCANNING)
wpa_supplicant_set_state(wpa_s,
wpa_s->scan_prev_wpa_state);
wpa_msg(wpa_s, MSG_INFO, WPA_EVENT_SCAN_FAILED "ret=%d%s",
ret, retry ? " retry=1" : "");
radio_work_done(work);
if (retry) {
/* 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);
}
return;
}
os_get_reltime(&wpa_s->scan_trigger_time);
wpa_s->scan_runs++;
wpa_s->normal_scans++;
wpa_s->own_scan_requested = 1;
wpa_s->clear_driver_scan_cache = 0;
wpa_s->scan_work = work;
}
/**
* 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)
{
struct wpa_driver_scan_params *ctx;
if (wpa_s->scan_work) {
wpa_dbg(wpa_s, MSG_INFO, "Reject scan trigger since one is already pending");
return -1;
}
ctx = wpa_scan_clone_params(params);
if (ctx == NULL)
return -1;
if (radio_add_work(wpa_s, 0, "scan", 0, wpas_trigger_scan_cb, ctx) < 0)
{
wpa_scan_free_params(ctx);
return -1;
}
return 0;
}
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_calloc(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_calloc(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++;
}
if (params->freqs == NULL && wpa_s->p2p_in_invitation) {
/*
* Optimize scan based on GO information during persistent
* group reinvocation
*/
if (wpa_s->p2p_in_invitation < 5 &&
wpa_s->p2p_invite_go_freq > 0) {
wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Scan only GO preferred frequency %d MHz during invitation",
wpa_s->p2p_invite_go_freq);
params->freqs = os_calloc(2, sizeof(int));
if (params->freqs)
params->freqs[0] = wpa_s->p2p_invite_go_freq;
}
wpa_s->p2p_in_invitation++;
if (wpa_s->p2p_in_invitation > 20) {
/*
* This should not really happen since the variable is
* cleared on group removal, but if it does happen, make
* sure we do not get stuck in special invitation scan
* mode.
*/
wpa_dbg(wpa_s, MSG_DEBUG, "P2P: Clear p2p_in_invitation");
wpa_s->p2p_in_invitation = 0;
}
}
#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_calloc(2, sizeof(int));
if (params->freqs)
params->freqs[0] = wpa_s->wps_freq;
wpa_s->after_wps--;
} else if (wpa_s->after_wps)
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_calloc(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)
{
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;
u8 ext_capab[18];
int ext_capab_len;
#ifdef CONFIG_WPS
int wps = 0;
enum wps_request_type req_type = WPS_REQ_ENROLLEE_INFO;
#endif /* CONFIG_WPS */
ext_capab_len = wpas_build_ext_capab(wpa_s, ext_capab,
sizeof(ext_capab));
if (ext_capab_len > 0 &&
wpabuf_resize(&extra_ie, ext_capab_len) == 0)
wpabuf_put_data(extra_ie, ext_capab, ext_capab_len);
#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 */
wpa_supplicant_mesh_add_scan_ie(wpa_s, &extra_ie);
#endif /* CONFIG_WPS */
#ifdef CONFIG_HS20
if (wpa_s->conf->hs20 && wpabuf_resize(&extra_ie, 7) == 0)
wpas_hs20_add_indication(extra_ie, -1);
#endif /* CONFIG_HS20 */
#ifdef CONFIG_FST
if (wpa_s->fst_ies &&
wpabuf_resize(&extra_ie, wpabuf_len(wpa_s->fst_ies)) == 0)
wpabuf_put_buf(extra_ie, wpa_s->fst_ies);
#endif /* CONFIG_FST */
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_calloc(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_set_scan_ssids(struct wpa_supplicant *wpa_s,
struct wpa_driver_scan_params *params,
size_t max_ssids)
{
unsigned int i;
struct wpa_ssid *ssid;
for (i = 0; i < wpa_s->scan_id_count; i++) {
unsigned int j;
ssid = wpa_config_get_network(wpa_s->conf, wpa_s->scan_id[i]);
if (!ssid || !ssid->scan_ssid)
continue;
for (j = 0; j < params->num_ssids; j++) {
if (params->ssids[j].ssid_len == ssid->ssid_len &&
params->ssids[j].ssid &&
os_memcmp(params->ssids[j].ssid, ssid->ssid,
ssid->ssid_len) == 0)
break;
}
if (j < params->num_ssids)
continue; /* already in the list */
if (params->num_ssids + 1 > max_ssids) {
wpa_printf(MSG_DEBUG,
"Over max scan SSIDs for manual request");
break;
}
wpa_printf(MSG_DEBUG, "Scan SSID (manual request): %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++;
}
wpa_s->scan_id_count = 0;
}
static int wpa_set_ssids_from_scan_req(struct wpa_supplicant *wpa_s,
struct wpa_driver_scan_params *params,
size_t max_ssids)
{
unsigned int i;
if (wpa_s->ssids_from_scan_req == NULL ||
wpa_s->num_ssids_from_scan_req == 0)
return 0;
if (wpa_s->num_ssids_from_scan_req > max_ssids) {
wpa_s->num_ssids_from_scan_req = max_ssids;
wpa_printf(MSG_DEBUG, "Over max scan SSIDs from scan req: %u",
(unsigned int) max_ssids);
}
for (i = 0; i < wpa_s->num_ssids_from_scan_req; i++) {
params->ssids[i].ssid = wpa_s->ssids_from_scan_req[i].ssid;
params->ssids[i].ssid_len =
wpa_s->ssids_from_scan_req[i].ssid_len;
wpa_hexdump_ascii(MSG_DEBUG, "specific SSID",
params->ssids[i].ssid,
params->ssids[i].ssid_len);
}
params->num_ssids = wpa_s->num_ssids_from_scan_req;
wpa_s->num_ssids_from_scan_req = 0;
return 1;
}
static void wpa_supplicant_scan(void *eloop_ctx, void *timeout_ctx)
{
struct wpa_supplicant *wpa_s = eloop_ctx;
struct wpa_ssid *ssid;
int ret, p2p_in_prog;
struct wpabuf *extra_ie = NULL;
struct wpa_driver_scan_params params;
struct wpa_driver_scan_params *scan_params;
size_t max_ssids;
int connect_without_scan = 0;
if (wpa_s->pno || wpa_s->pno_sched_pending) {
wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - PNO is in progress");
return;
}
if (wpa_s->wpa_state == WPA_INTERFACE_DISABLED) {
wpa_dbg(wpa_s, MSG_DEBUG, "Skip scan - interface disabled");
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);
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);
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;
}
ssid = NULL;
if (wpa_s->scan_req != MANUAL_SCAN_REQ &&
wpa_s->connect_without_scan) {
connect_without_scan = 1;
for (ssid = wpa_s->conf->ssid; ssid; ssid = ssid->next) {
if (ssid == wpa_s->connect_without_scan)
break;
}
}
p2p_in_prog = wpas_p2p_in_progress(wpa_s);
if (p2p_in_prog && p2p_in_prog != 2 &&
(!ssid ||
(ssid->mode != WPAS_MODE_AP && ssid->mode != WPAS_MODE_P2P_GO))) {
wpa_dbg(wpa_s, MSG_DEBUG, "Delay station mode scan while P2P operation is in progress");
wpa_supplicant_req_scan(wpa_s, 5, 0);
return;
}
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;
if (connect_without_scan) {
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;
}
}
os_memset(&params, 0, sizeof(params));
wpa_s->scan_prev_wpa_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_set_ssids_from_scan_req(wpa_s, &params, max_ssids)) {
wpa_printf(MSG_DEBUG, "Use specific SSIDs from SCAN command");
goto ssid_list_set;
}
#ifdef CONFIG_P2P
if ((wpa_s->p2p_in_provisioning || wpa_s->show_group_started) &&
wpa_s->go_params && !wpa_s->conf->passive_scan) {
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;
}
if (wpa_s->p2p_in_invitation) {
if (wpa_s->current_ssid) {
wpa_printf(MSG_DEBUG, "P2P: Use specific SSID for scan during invitation");
params.ssids[0].ssid = wpa_s->current_ssid->ssid;
params.ssids[0].ssid_len =
wpa_s->current_ssid->ssid_len;
params.num_ssids = 1;
} else {
wpa_printf(MSG_DEBUG, "P2P: No specific SSID known for scan during invitation");
}
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 &&
#ifdef CONFIG_AP
!wpa_s->ap_iface &&
#endif /* CONFIG_AP */
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 if (wpa_s->reattach && wpa_s->current_ssid != NULL) {
/*
* Perform single-channel single-SSID scan for
* reassociate-to-same-BSS operation.
*/
/* Setup SSID */
ssid = wpa_s->current_ssid;
wpa_hexdump_ascii(MSG_DEBUG, "Scan SSID",
ssid->ssid, ssid->ssid_len);
params.ssids[0].ssid = ssid->ssid;
params.ssids[0].ssid_len = ssid->ssid_len;
params.num_ssids = 1;
/*
* Allocate memory for frequency array, allocate one extra
* slot for the zero-terminator.
*/
params.freqs = os_malloc(sizeof(int) * 2);
if (params.freqs == NULL) {
wpa_dbg(wpa_s, MSG_ERROR, "Memory allocation failed");
return;
}
params.freqs[0] = wpa_s->assoc_freq;
params.freqs[1] = 0;
/*
* Reset the reattach flag so that we fall back to full scan if
* this scan fails.
*/
wpa_s->reattach = 0;
} 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;
}
if (wpa_s->scan_id_count &&
wpa_s->last_scan_req == MANUAL_SCAN_REQ)
wpa_set_scan_ssids(wpa_s, &params, max_ssids);
for (tssid = wpa_s->conf->ssid;
wpa_s->last_scan_req != MANUAL_SCAN_REQ && 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 if (wpa_s->last_scan_req == MANUAL_SCAN_REQ &&
wpa_s->manual_scan_passive && params.num_ssids == 0) {
wpa_dbg(wpa_s, MSG_DEBUG, "Use passive scan based on manual request");
} else if (wpa_s->conf->passive_scan) {
wpa_dbg(wpa_s, MSG_DEBUG,
"Use passive scan based on configuration");
} else {
wpa_s->prev_scan_ssid = WILDCARD_SSID_SCAN;
params.num_ssids++;
wpa_dbg(wpa_s, MSG_DEBUG, "Starting AP scan for wildcard "
"SSID");
}
ssid_list_set:
wpa_supplicant_optimize_freqs(wpa_s, &params);
extra_ie = wpa_supplicant_extra_ies(wpa_s);
if (wpa_s->last_scan_req == MANUAL_SCAN_REQ &&
wpa_s->manual_scan_only_new) {
wpa_printf(MSG_DEBUG,
"Request driver to clear scan cache due to manual only_new=1 scan");
params.only_new_results = 1;
}
if (wpa_s->last_scan_req == MANUAL_SCAN_REQ && params.freqs == NULL &&
wpa_s->manual_scan_freqs) {
wpa_dbg(wpa_s, MSG_DEBUG, "Limit manual scan to specified channels");
params.freqs = wpa_s->manual_scan_freqs;
wpa_s->manual_scan_freqs = NULL;
}
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->p2p_in_invitation ||
(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 */
if (wpa_s->mac_addr_rand_enable & MAC_ADDR_RAND_SCAN) {
params.mac_addr_rand = 1;
if (wpa_s->mac_addr_scan) {
params.mac_addr = wpa_s->mac_addr_scan;
params.mac_addr_mask = wpa_s->mac_addr_scan + ETH_ALEN;
}
}
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);
if (ret && wpa_s->last_scan_req == MANUAL_SCAN_REQ && params.freqs &&
!wpa_s->manual_scan_freqs) {
/* Restore manual_scan_freqs for the next attempt */
wpa_s->manual_scan_freqs = params.freqs;
params.freqs = NULL;
}
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 (wpa_s->scan_prev_wpa_state != wpa_s->wpa_state)
wpa_supplicant_set_state(wpa_s,
wpa_s->scan_prev_wpa_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;
#ifdef CONFIG_INTERWORKING
wpa_s->interworking_fast_assoc_tried = 0;
#endif /* CONFIG_INTERWORKING */
}
}
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)
{
int res;
if (wpa_s->p2p_mgmt) {
wpa_dbg(wpa_s, MSG_DEBUG,
"Ignore scan request (%d.%06d sec) on p2p_mgmt interface",
sec, usec);
return;
}
res = eloop_deplete_timeout(sec, usec, wpa_supplicant_scan, wpa_s,
NULL);
if (res == 1) {
wpa_dbg(wpa_s, MSG_DEBUG, "Rescheduling scan request: %d.%06d sec",
sec, usec);
} else if (res == 0) {
wpa_dbg(wpa_s, MSG_DEBUG, "Ignore new scan request for %d.%06d sec since an earlier request is scheduled to trigger sooner",
sec, usec);
} else {
wpa_dbg(wpa_s, MSG_DEBUG, "Setting scan request: %d.%06d sec",
sec, usec);
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_calloc(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);
}
if (wpa_s->conf->filter_rssi)
params.filter_rssi = wpa_s->conf->filter_rssi;
/* 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);
}
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);
if (wpa_s->mac_addr_rand_enable & MAC_ADDR_RAND_SCHED_SCAN) {
params.mac_addr_rand = 1;
if (wpa_s->mac_addr_sched_scan) {
params.mac_addr = wpa_s->mac_addr_sched_scan;
params.mac_addr_mask = wpa_s->mac_addr_sched_scan +
ETH_ALEN;
}
}
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);
}
/**
* 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
Improve BSS selection with default noise floor values When noise floor measurements are not available, compute SNR using default values for the noise floor. This helps steer us towards 5 GHz BSSes in high signal strength environments. In more detail... Existing code prefers a 5 GHz BSS when the 5 GHz BSS's signal strength is "close" to that of the 2.4 GHz BSS, or when both SNRs are large. However, the mwifiex driver does not provide noise floor measurements, so we can't compute SNRs. Because mwifiex doesn't provide NF measurements, the "large SNR" code wasn't effective. By using default values for the noise floor, we can again compute SNRs, and decide that the SNR is high enough that we shouldn't worry about the exact difference in SNR. The default noise floor values (one for 2.4 GHz, and one for 5 GHz) were chosen by measurement in a noisy environment, so they should be conservative. Note that while this patch is motivated by mwifiex, it affects ath9k as well. Although ath9k provides noise floor measurements in general, it will sometimes fail to provide a measurement for one or more specific channels. As a result of this patch, we'll always compare BSSes based on SNR (either measured or estimated), rather than sometimes comparing based on signal strength. ("Always" assumes that the WPA_SCAN_LEVEL_DBM flag is set. It is for mwifiex and ath9k.) While there: - fix a whitespace issue (spaces -> tab) - clean up existing comments - update dump_scan_res to indicate whether the noise floor is measured, or default Signed-hostap: mukesh agrawal <quiche@chromium.org>
2014-04-09 02:54:49 +02:00
#define IS_5GHZ(n) (n > 4000)
/* 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 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;
int snr_a, snr_b, snr_a_full, snr_b_full;
/* 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;
Improve BSS selection with default noise floor values When noise floor measurements are not available, compute SNR using default values for the noise floor. This helps steer us towards 5 GHz BSSes in high signal strength environments. In more detail... Existing code prefers a 5 GHz BSS when the 5 GHz BSS's signal strength is "close" to that of the 2.4 GHz BSS, or when both SNRs are large. However, the mwifiex driver does not provide noise floor measurements, so we can't compute SNRs. Because mwifiex doesn't provide NF measurements, the "large SNR" code wasn't effective. By using default values for the noise floor, we can again compute SNRs, and decide that the SNR is high enough that we shouldn't worry about the exact difference in SNR. The default noise floor values (one for 2.4 GHz, and one for 5 GHz) were chosen by measurement in a noisy environment, so they should be conservative. Note that while this patch is motivated by mwifiex, it affects ath9k as well. Although ath9k provides noise floor measurements in general, it will sometimes fail to provide a measurement for one or more specific channels. As a result of this patch, we'll always compare BSSes based on SNR (either measured or estimated), rather than sometimes comparing based on signal strength. ("Always" assumes that the WPA_SCAN_LEVEL_DBM flag is set. It is for mwifiex and ath9k.) While there: - fix a whitespace issue (spaces -> tab) - clean up existing comments - update dump_scan_res to indicate whether the noise floor is measured, or default Signed-hostap: mukesh agrawal <quiche@chromium.org>
2014-04-09 02:54:49 +02:00
if (wa->flags & wb->flags & WPA_SCAN_LEVEL_DBM) {
snr_a_full = wa->snr;
snr_a = MIN(wa->snr, GREAT_SNR);
snr_b_full = wb->snr;
snr_b = MIN(wb->snr, GREAT_SNR);
} else {
Improve BSS selection with default noise floor values When noise floor measurements are not available, compute SNR using default values for the noise floor. This helps steer us towards 5 GHz BSSes in high signal strength environments. In more detail... Existing code prefers a 5 GHz BSS when the 5 GHz BSS's signal strength is "close" to that of the 2.4 GHz BSS, or when both SNRs are large. However, the mwifiex driver does not provide noise floor measurements, so we can't compute SNRs. Because mwifiex doesn't provide NF measurements, the "large SNR" code wasn't effective. By using default values for the noise floor, we can again compute SNRs, and decide that the SNR is high enough that we shouldn't worry about the exact difference in SNR. The default noise floor values (one for 2.4 GHz, and one for 5 GHz) were chosen by measurement in a noisy environment, so they should be conservative. Note that while this patch is motivated by mwifiex, it affects ath9k as well. Although ath9k provides noise floor measurements in general, it will sometimes fail to provide a measurement for one or more specific channels. As a result of this patch, we'll always compare BSSes based on SNR (either measured or estimated), rather than sometimes comparing based on signal strength. ("Always" assumes that the WPA_SCAN_LEVEL_DBM flag is set. It is for mwifiex and ath9k.) While there: - fix a whitespace issue (spaces -> tab) - clean up existing comments - update dump_scan_res to indicate whether the noise floor is measured, or default Signed-hostap: mukesh agrawal <quiche@chromium.org>
2014-04-09 02:54:49 +02:00
/* Level is not in dBm, so we can't calculate
* SNR. Just use raw level (units unknown). */
snr_a = snr_a_full = wa->level;
snr_b = snr_b_full = wb->level;
}
Improve BSS selection with default noise floor values When noise floor measurements are not available, compute SNR using default values for the noise floor. This helps steer us towards 5 GHz BSSes in high signal strength environments. In more detail... Existing code prefers a 5 GHz BSS when the 5 GHz BSS's signal strength is "close" to that of the 2.4 GHz BSS, or when both SNRs are large. However, the mwifiex driver does not provide noise floor measurements, so we can't compute SNRs. Because mwifiex doesn't provide NF measurements, the "large SNR" code wasn't effective. By using default values for the noise floor, we can again compute SNRs, and decide that the SNR is high enough that we shouldn't worry about the exact difference in SNR. The default noise floor values (one for 2.4 GHz, and one for 5 GHz) were chosen by measurement in a noisy environment, so they should be conservative. Note that while this patch is motivated by mwifiex, it affects ath9k as well. Although ath9k provides noise floor measurements in general, it will sometimes fail to provide a measurement for one or more specific channels. As a result of this patch, we'll always compare BSSes based on SNR (either measured or estimated), rather than sometimes comparing based on signal strength. ("Always" assumes that the WPA_SCAN_LEVEL_DBM flag is set. It is for mwifiex and ath9k.) While there: - fix a whitespace issue (spaces -> tab) - clean up existing comments - update dump_scan_res to indicate whether the noise floor is measured, or default Signed-hostap: mukesh agrawal <quiche@chromium.org>
2014-04-09 02:54:49 +02:00
/* if SNR is close, decide by max rate or frequency band */
if ((snr_a && snr_b && abs(snr_b - snr_a) < 5) ||
(wa->qual && wb->qual && abs(wb->qual - wa->qual) < 10)) {
if (wa->est_throughput != wb->est_throughput)
return wb->est_throughput - wa->est_throughput;
if (IS_5GHZ(wa->freq) ^ IS_5GHZ(wb->freq))
return IS_5GHZ(wa->freq) ? -1 : 1;
}
/* 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_full == snr_a_full)
return wb->qual - wa->qual;
return snr_b_full - snr_a_full;
#undef MIN
}
#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;
Improve BSS selection with default noise floor values When noise floor measurements are not available, compute SNR using default values for the noise floor. This helps steer us towards 5 GHz BSSes in high signal strength environments. In more detail... Existing code prefers a 5 GHz BSS when the 5 GHz BSS's signal strength is "close" to that of the 2.4 GHz BSS, or when both SNRs are large. However, the mwifiex driver does not provide noise floor measurements, so we can't compute SNRs. Because mwifiex doesn't provide NF measurements, the "large SNR" code wasn't effective. By using default values for the noise floor, we can again compute SNRs, and decide that the SNR is high enough that we shouldn't worry about the exact difference in SNR. The default noise floor values (one for 2.4 GHz, and one for 5 GHz) were chosen by measurement in a noisy environment, so they should be conservative. Note that while this patch is motivated by mwifiex, it affects ath9k as well. Although ath9k provides noise floor measurements in general, it will sometimes fail to provide a measurement for one or more specific channels. As a result of this patch, we'll always compare BSSes based on SNR (either measured or estimated), rather than sometimes comparing based on signal strength. ("Always" assumes that the WPA_SCAN_LEVEL_DBM flag is set. It is for mwifiex and ath9k.) While there: - fix a whitespace issue (spaces -> tab) - clean up existing comments - update dump_scan_res to indicate whether the noise floor is measured, or default Signed-hostap: mukesh agrawal <quiche@chromium.org>
2014-04-09 02:54:49 +02:00
if (r->flags & WPA_SCAN_LEVEL_DBM) {
int noise_valid = !(r->flags & WPA_SCAN_NOISE_INVALID);
wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
"noise=%d%s level=%d snr=%d%s flags=0x%x age=%u est=%u",
MAC2STR(r->bssid), r->freq, r->qual,
Improve BSS selection with default noise floor values When noise floor measurements are not available, compute SNR using default values for the noise floor. This helps steer us towards 5 GHz BSSes in high signal strength environments. In more detail... Existing code prefers a 5 GHz BSS when the 5 GHz BSS's signal strength is "close" to that of the 2.4 GHz BSS, or when both SNRs are large. However, the mwifiex driver does not provide noise floor measurements, so we can't compute SNRs. Because mwifiex doesn't provide NF measurements, the "large SNR" code wasn't effective. By using default values for the noise floor, we can again compute SNRs, and decide that the SNR is high enough that we shouldn't worry about the exact difference in SNR. The default noise floor values (one for 2.4 GHz, and one for 5 GHz) were chosen by measurement in a noisy environment, so they should be conservative. Note that while this patch is motivated by mwifiex, it affects ath9k as well. Although ath9k provides noise floor measurements in general, it will sometimes fail to provide a measurement for one or more specific channels. As a result of this patch, we'll always compare BSSes based on SNR (either measured or estimated), rather than sometimes comparing based on signal strength. ("Always" assumes that the WPA_SCAN_LEVEL_DBM flag is set. It is for mwifiex and ath9k.) While there: - fix a whitespace issue (spaces -> tab) - clean up existing comments - update dump_scan_res to indicate whether the noise floor is measured, or default Signed-hostap: mukesh agrawal <quiche@chromium.org>
2014-04-09 02:54:49 +02:00
r->noise, noise_valid ? "" : "~", r->level,
r->snr, r->snr >= GREAT_SNR ? "*" : "",
r->flags,
r->age, r->est_throughput);
} else {
wpa_printf(MSG_EXCESSIVE, MACSTR " freq=%d qual=%d "
"noise=%d level=%d flags=0x%x age=%u est=%u",
MAC2STR(r->bssid), r->freq, r->qual,
r->noise, r->level, r->flags, r->age,
r->est_throughput);
}
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;
}
}
Improve BSS selection with default noise floor values When noise floor measurements are not available, compute SNR using default values for the noise floor. This helps steer us towards 5 GHz BSSes in high signal strength environments. In more detail... Existing code prefers a 5 GHz BSS when the 5 GHz BSS's signal strength is "close" to that of the 2.4 GHz BSS, or when both SNRs are large. However, the mwifiex driver does not provide noise floor measurements, so we can't compute SNRs. Because mwifiex doesn't provide NF measurements, the "large SNR" code wasn't effective. By using default values for the noise floor, we can again compute SNRs, and decide that the SNR is high enough that we shouldn't worry about the exact difference in SNR. The default noise floor values (one for 2.4 GHz, and one for 5 GHz) were chosen by measurement in a noisy environment, so they should be conservative. Note that while this patch is motivated by mwifiex, it affects ath9k as well. Although ath9k provides noise floor measurements in general, it will sometimes fail to provide a measurement for one or more specific channels. As a result of this patch, we'll always compare BSSes based on SNR (either measured or estimated), rather than sometimes comparing based on signal strength. ("Always" assumes that the WPA_SCAN_LEVEL_DBM flag is set. It is for mwifiex and ath9k.) While there: - fix a whitespace issue (spaces -> tab) - clean up existing comments - update dump_scan_res to indicate whether the noise floor is measured, or default Signed-hostap: mukesh agrawal <quiche@chromium.org>
2014-04-09 02:54:49 +02:00
/*
* Noise floor values to use when we have signal strength
* measurements, but no noise floor measurments. These values were
* measured in an office environment with many APs.
*/
#define DEFAULT_NOISE_FLOOR_2GHZ (-89)
#define DEFAULT_NOISE_FLOOR_5GHZ (-92)
static void scan_snr(struct wpa_scan_res *res)
{
if (res->flags & WPA_SCAN_NOISE_INVALID) {
res->noise = IS_5GHZ(res->freq) ?
DEFAULT_NOISE_FLOOR_5GHZ :
DEFAULT_NOISE_FLOOR_2GHZ;
}
if (res->flags & WPA_SCAN_LEVEL_DBM) {
res->snr = res->level - res->noise;
} else {
/* Level is not in dBm, so we can't calculate
* SNR. Just use raw level (units unknown). */
res->snr = res->level;
}
}
static unsigned int max_ht20_rate(int snr)
{
if (snr < 6)
return 6500; /* HT20 MCS0 */
if (snr < 8)
return 13000; /* HT20 MCS1 */
if (snr < 13)
return 19500; /* HT20 MCS2 */
if (snr < 17)
return 26000; /* HT20 MCS3 */
if (snr < 20)
return 39000; /* HT20 MCS4 */
if (snr < 23)
return 52000; /* HT20 MCS5 */
if (snr < 24)
return 58500; /* HT20 MCS6 */
return 65000; /* HT20 MCS7 */
}
static unsigned int max_ht40_rate(int snr)
{
if (snr < 3)
return 13500; /* HT40 MCS0 */
if (snr < 6)
return 27000; /* HT40 MCS1 */
if (snr < 10)
return 40500; /* HT40 MCS2 */
if (snr < 15)
return 54000; /* HT40 MCS3 */
if (snr < 17)
return 81000; /* HT40 MCS4 */
if (snr < 22)
return 108000; /* HT40 MCS5 */
if (snr < 24)
return 121500; /* HT40 MCS6 */
return 135000; /* HT40 MCS7 */
}
static unsigned int max_vht80_rate(int snr)
{
if (snr < 1)
return 0;
if (snr < 2)
return 29300; /* VHT80 MCS0 */
if (snr < 5)
return 58500; /* VHT80 MCS1 */
if (snr < 9)
return 87800; /* VHT80 MCS2 */
if (snr < 11)
return 117000; /* VHT80 MCS3 */
if (snr < 15)
return 175500; /* VHT80 MCS4 */
if (snr < 16)
return 234000; /* VHT80 MCS5 */
if (snr < 18)
return 263300; /* VHT80 MCS6 */
if (snr < 20)
return 292500; /* VHT80 MCS7 */
if (snr < 22)
return 351000; /* VHT80 MCS8 */
return 390000; /* VHT80 MCS9 */
}
static void scan_est_throughput(struct wpa_supplicant *wpa_s,
struct wpa_scan_res *res)
{
enum local_hw_capab capab = wpa_s->hw_capab;
int rate; /* max legacy rate in 500 kb/s units */
const u8 *ie;
unsigned int est, tmp;
int snr = res->snr;
if (res->est_throughput)
return;
/* Get maximum legacy rate */
rate = wpa_scan_get_max_rate(res);
/* Limit based on estimated SNR */
if (rate > 1 * 2 && snr < 1)
rate = 1 * 2;
else if (rate > 2 * 2 && snr < 4)
rate = 2 * 2;
else if (rate > 6 * 2 && snr < 5)
rate = 6 * 2;
else if (rate > 9 * 2 && snr < 6)
rate = 9 * 2;
else if (rate > 12 * 2 && snr < 7)
rate = 12 * 2;
else if (rate > 18 * 2 && snr < 10)
rate = 18 * 2;
else if (rate > 24 * 2 && snr < 11)
rate = 24 * 2;
else if (rate > 36 * 2 && snr < 15)
rate = 36 * 2;
else if (rate > 48 * 2 && snr < 19)
rate = 48 * 2;
else if (rate > 54 * 2 && snr < 21)
rate = 54 * 2;
est = rate * 500;
if (capab == CAPAB_HT || capab == CAPAB_HT40 || capab == CAPAB_VHT) {
ie = wpa_scan_get_ie(res, WLAN_EID_HT_CAP);
if (ie) {
tmp = max_ht20_rate(snr);
if (tmp > est)
est = tmp;
}
}
if (capab == CAPAB_HT40 || capab == CAPAB_VHT) {
ie = wpa_scan_get_ie(res, WLAN_EID_HT_OPERATION);
if (ie && ie[1] >= 2 &&
(ie[3] & HT_INFO_HT_PARAM_SECONDARY_CHNL_OFF_MASK)) {
tmp = max_ht40_rate(snr);
if (tmp > est)
est = tmp;
}
}
if (capab == CAPAB_VHT) {
/* Use +1 to assume VHT is always faster than HT */
ie = wpa_scan_get_ie(res, WLAN_EID_VHT_CAP);
if (ie) {
tmp = max_ht20_rate(snr) + 1;
if (tmp > est)
est = tmp;
ie = wpa_scan_get_ie(res, WLAN_EID_HT_OPERATION);
if (ie && ie[1] >= 2 &&
(ie[3] &
HT_INFO_HT_PARAM_SECONDARY_CHNL_OFF_MASK)) {
tmp = max_ht40_rate(snr) + 1;
if (tmp > est)
est = tmp;
}
ie = wpa_scan_get_ie(res, WLAN_EID_VHT_OPERATION);
if (ie && ie[1] >= 1 &&
(ie[2] & VHT_OPMODE_CHANNEL_WIDTH_MASK)) {
tmp = max_vht80_rate(snr) + 1;
if (tmp > est)
est = tmp;
}
}
}
/* TODO: channel utilization and AP load (e.g., from AP Beacon) */
res->est_throughput = est;
}
/**
* 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);
Improve BSS selection with default noise floor values When noise floor measurements are not available, compute SNR using default values for the noise floor. This helps steer us towards 5 GHz BSSes in high signal strength environments. In more detail... Existing code prefers a 5 GHz BSS when the 5 GHz BSS's signal strength is "close" to that of the 2.4 GHz BSS, or when both SNRs are large. However, the mwifiex driver does not provide noise floor measurements, so we can't compute SNRs. Because mwifiex doesn't provide NF measurements, the "large SNR" code wasn't effective. By using default values for the noise floor, we can again compute SNRs, and decide that the SNR is high enough that we shouldn't worry about the exact difference in SNR. The default noise floor values (one for 2.4 GHz, and one for 5 GHz) were chosen by measurement in a noisy environment, so they should be conservative. Note that while this patch is motivated by mwifiex, it affects ath9k as well. Although ath9k provides noise floor measurements in general, it will sometimes fail to provide a measurement for one or more specific channels. As a result of this patch, we'll always compare BSSes based on SNR (either measured or estimated), rather than sometimes comparing based on signal strength. ("Always" assumes that the WPA_SCAN_LEVEL_DBM flag is set. It is for mwifiex and ath9k.) While there: - fix a whitespace issue (spaces -> tab) - clean up existing comments - update dump_scan_res to indicate whether the noise floor is measured, or default Signed-hostap: mukesh agrawal <quiche@chromium.org>
2014-04-09 02:54:49 +02:00
for (i = 0; i < scan_res->num; i++) {
struct wpa_scan_res *scan_res_item = scan_res->res[i];
scan_snr(scan_res_item);
scan_est_throughput(wpa_s, scan_res_item);
Improve BSS selection with default noise floor values When noise floor measurements are not available, compute SNR using default values for the noise floor. This helps steer us towards 5 GHz BSSes in high signal strength environments. In more detail... Existing code prefers a 5 GHz BSS when the 5 GHz BSS's signal strength is "close" to that of the 2.4 GHz BSS, or when both SNRs are large. However, the mwifiex driver does not provide noise floor measurements, so we can't compute SNRs. Because mwifiex doesn't provide NF measurements, the "large SNR" code wasn't effective. By using default values for the noise floor, we can again compute SNRs, and decide that the SNR is high enough that we shouldn't worry about the exact difference in SNR. The default noise floor values (one for 2.4 GHz, and one for 5 GHz) were chosen by measurement in a noisy environment, so they should be conservative. Note that while this patch is motivated by mwifiex, it affects ath9k as well. Although ath9k provides noise floor measurements in general, it will sometimes fail to provide a measurement for one or more specific channels. As a result of this patch, we'll always compare BSSes based on SNR (either measured or estimated), rather than sometimes comparing based on signal strength. ("Always" assumes that the WPA_SCAN_LEVEL_DBM flag is set. It is for mwifiex and ath9k.) While there: - fix a whitespace issue (spaces -> tab) - clean up existing comments - update dump_scan_res to indicate whether the noise floor is measured, or default Signed-hostap: mukesh agrawal <quiche@chromium.org>
2014-04-09 02:54:49 +02:00
}
#ifdef CONFIG_WPS
if (wpas_wps_searching(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");
if (wpa_s->last_scan_req == MANUAL_SCAN_REQ &&
wpa_s->manual_scan_use_id && wpa_s->own_scan_running) {
wpa_msg_ctrl(wpa_s, MSG_INFO, WPA_EVENT_SCAN_RESULTS "id=%u",
wpa_s->manual_scan_id);
wpa_s->manual_scan_use_id = 0;
} else {
wpa_msg_ctrl(wpa_s, MSG_INFO, WPA_EVENT_SCAN_RESULTS);
}
wpas_notify_scan_results(wpa_s);
wpas_notify_scan_done(wpa_s, 1);
if (wpa_s->scan_work) {
struct wpa_radio_work *work = wpa_s->scan_work;
wpa_s->scan_work = NULL;
radio_work_done(work);
}
}
int wpas_scan_scheduled(struct wpa_supplicant *wpa_s)
{
return eloop_is_timeout_registered(wpa_supplicant_scan, wpa_s, NULL);
}
struct wpa_driver_scan_params *
wpa_scan_clone_params(const struct wpa_driver_scan_params *src)
{
struct wpa_driver_scan_params *params;
size_t i;
u8 *n;
params = os_zalloc(sizeof(*params));
if (params == NULL)
return NULL;
for (i = 0; i < src->num_ssids; i++) {
if (src->ssids[i].ssid) {
n = os_malloc(src->ssids[i].ssid_len);
if (n == NULL)
goto failed;
os_memcpy(n, src->ssids[i].ssid,
src->ssids[i].ssid_len);
params->ssids[i].ssid = n;
params->ssids[i].ssid_len = src->ssids[i].ssid_len;
}
}
params->num_ssids = src->num_ssids;
if (src->extra_ies) {
n = os_malloc(src->extra_ies_len);
if (n == NULL)
goto failed;
os_memcpy(n, src->extra_ies, src->extra_ies_len);
params->extra_ies = n;
params->extra_ies_len = src->extra_ies_len;
}
if (src->freqs) {
int len = int_array_len(src->freqs);
params->freqs = os_malloc((len + 1) * sizeof(int));
if (params->freqs == NULL)
goto failed;
os_memcpy(params->freqs, src->freqs, (len + 1) * sizeof(int));
}
if (src->filter_ssids) {
params->filter_ssids = os_malloc(sizeof(*params->filter_ssids) *
src->num_filter_ssids);
if (params->filter_ssids == NULL)
goto failed;
os_memcpy(params->filter_ssids, src->filter_ssids,
sizeof(*params->filter_ssids) *
src->num_filter_ssids);
params->num_filter_ssids = src->num_filter_ssids;
}
params->filter_rssi = src->filter_rssi;
params->p2p_probe = src->p2p_probe;
params->only_new_results = src->only_new_results;
params->low_priority = src->low_priority;
if (src->mac_addr_rand) {
params->mac_addr_rand = src->mac_addr_rand;
if (src->mac_addr && src->mac_addr_mask) {
u8 *mac_addr;
mac_addr = os_malloc(2 * ETH_ALEN);
if (!mac_addr)
goto failed;
os_memcpy(mac_addr, src->mac_addr, ETH_ALEN);
os_memcpy(mac_addr + ETH_ALEN, src->mac_addr_mask,
ETH_ALEN);
params->mac_addr = mac_addr;
params->mac_addr_mask = mac_addr + ETH_ALEN;
}
}
return params;
failed:
wpa_scan_free_params(params);
return NULL;
}
void wpa_scan_free_params(struct wpa_driver_scan_params *params)
{
size_t i;
if (params == NULL)
return;
for (i = 0; i < params->num_ssids; i++)
os_free((u8 *) params->ssids[i].ssid);
os_free((u8 *) params->extra_ies);
os_free(params->freqs);
os_free(params->filter_ssids);
/*
* Note: params->mac_addr_mask points to same memory allocation and
* must not be freed separately.
*/
os_free((u8 *) params->mac_addr);
os_free(params);
}
int wpas_start_pno(struct wpa_supplicant *wpa_s)
{
int ret, interval, prio;
size_t i, num_ssid, num_match_ssid;
struct wpa_ssid *ssid;
struct wpa_driver_scan_params params;
if (!wpa_s->sched_scan_supported)
return -1;
if (wpa_s->pno || wpa_s->pno_sched_pending)
return 0;
if ((wpa_s->wpa_state > WPA_SCANNING) &&
(wpa_s->wpa_state <= WPA_COMPLETED)) {
wpa_printf(MSG_ERROR, "PNO: In assoc process");
return -EAGAIN;
}
if (wpa_s->wpa_state == WPA_SCANNING) {
wpa_supplicant_cancel_scan(wpa_s);
if (wpa_s->sched_scanning) {
wpa_printf(MSG_DEBUG, "Schedule PNO on completion of "
"ongoing sched scan");
wpa_supplicant_cancel_sched_scan(wpa_s);
wpa_s->pno_sched_pending = 1;
return 0;
}
}
os_memset(&params, 0, sizeof(params));
num_ssid = num_match_ssid = 0;
ssid = wpa_s->conf->ssid;
while (ssid) {
if (!wpas_network_disabled(wpa_s, ssid)) {
num_match_ssid++;
if (ssid->scan_ssid)
num_ssid++;
}
ssid = ssid->next;
}
if (num_match_ssid == 0) {
wpa_printf(MSG_DEBUG, "PNO: No configured SSIDs");
return -1;
}
if (num_match_ssid > num_ssid) {
params.num_ssids++; /* wildcard */
num_ssid++;
}
if (num_ssid > WPAS_MAX_SCAN_SSIDS) {
wpa_printf(MSG_DEBUG, "PNO: Use only the first %u SSIDs from "
"%u", WPAS_MAX_SCAN_SSIDS, (unsigned int) num_ssid);
num_ssid = WPAS_MAX_SCAN_SSIDS;
}
if (num_match_ssid > wpa_s->max_match_sets) {
num_match_ssid = wpa_s->max_match_sets;
wpa_dbg(wpa_s, MSG_DEBUG, "PNO: Too many SSIDs to match");
}
params.filter_ssids = os_calloc(num_match_ssid,
sizeof(struct wpa_driver_scan_filter));
if (params.filter_ssids == NULL)
return -1;
i = 0;
prio = 0;
ssid = wpa_s->conf->pssid[prio];
while (ssid) {
if (!wpas_network_disabled(wpa_s, ssid)) {
if (ssid->scan_ssid && params.num_ssids < num_ssid) {
params.ssids[params.num_ssids].ssid =
ssid->ssid;
params.ssids[params.num_ssids].ssid_len =
ssid->ssid_len;
params.num_ssids++;
}
os_memcpy(params.filter_ssids[i].ssid, ssid->ssid,
ssid->ssid_len);
params.filter_ssids[i].ssid_len = ssid->ssid_len;
params.num_filter_ssids++;
i++;
if (i == num_match_ssid)
break;
}
if (ssid->pnext)
ssid = ssid->pnext;
else if (prio + 1 == wpa_s->conf->num_prio)
break;
else
ssid = wpa_s->conf->pssid[++prio];
}
if (wpa_s->conf->filter_rssi)
params.filter_rssi = wpa_s->conf->filter_rssi;
interval = wpa_s->conf->sched_scan_interval ?
wpa_s->conf->sched_scan_interval : 10;
if (params.freqs == NULL && wpa_s->manual_sched_scan_freqs) {
wpa_dbg(wpa_s, MSG_DEBUG, "Limit sched scan to specified channels");
params.freqs = wpa_s->manual_sched_scan_freqs;
}
if (wpa_s->mac_addr_rand_enable & MAC_ADDR_RAND_PNO) {
params.mac_addr_rand = 1;
if (wpa_s->mac_addr_pno) {
params.mac_addr = wpa_s->mac_addr_pno;
params.mac_addr_mask = wpa_s->mac_addr_pno + ETH_ALEN;
}
}
ret = wpa_supplicant_start_sched_scan(wpa_s, &params, interval);
os_free(params.filter_ssids);
if (ret == 0)
wpa_s->pno = 1;
else
wpa_msg(wpa_s, MSG_ERROR, "Failed to schedule PNO");
return ret;
}
int wpas_stop_pno(struct wpa_supplicant *wpa_s)
{
int ret = 0;
if (!wpa_s->pno)
return 0;
ret = wpa_supplicant_stop_sched_scan(wpa_s);
wpa_s->pno = 0;
wpa_s->pno_sched_pending = 0;
if (wpa_s->wpa_state == WPA_SCANNING)
wpa_supplicant_req_scan(wpa_s, 0, 0);
return ret;
}
void wpas_mac_addr_rand_scan_clear(struct wpa_supplicant *wpa_s,
unsigned int type)
{
type &= MAC_ADDR_RAND_ALL;
wpa_s->mac_addr_rand_enable &= ~type;
if (type & MAC_ADDR_RAND_SCAN) {
os_free(wpa_s->mac_addr_scan);
wpa_s->mac_addr_scan = NULL;
}
if (type & MAC_ADDR_RAND_SCHED_SCAN) {
os_free(wpa_s->mac_addr_sched_scan);
wpa_s->mac_addr_sched_scan = NULL;
}
if (type & MAC_ADDR_RAND_PNO) {
os_free(wpa_s->mac_addr_pno);
wpa_s->mac_addr_pno = NULL;
}
}
int wpas_mac_addr_rand_scan_set(struct wpa_supplicant *wpa_s,
unsigned int type, const u8 *addr,
const u8 *mask)
{
u8 *tmp = NULL;
wpas_mac_addr_rand_scan_clear(wpa_s, type);
if (addr) {
tmp = os_malloc(2 * ETH_ALEN);
if (!tmp)
return -1;
os_memcpy(tmp, addr, ETH_ALEN);
os_memcpy(tmp + ETH_ALEN, mask, ETH_ALEN);
}
if (type == MAC_ADDR_RAND_SCAN) {
wpa_s->mac_addr_scan = tmp;
} else if (type == MAC_ADDR_RAND_SCHED_SCAN) {
wpa_s->mac_addr_sched_scan = tmp;
} else if (type == MAC_ADDR_RAND_PNO) {
wpa_s->mac_addr_pno = tmp;
} else {
wpa_printf(MSG_INFO,
"scan: Invalid MAC randomization type=0x%x",
type);
os_free(tmp);
return -1;
}
wpa_s->mac_addr_rand_enable |= type;
return 0;
}