/*
* libwebsockets - lws_netdev_wifi generic state handling
*
* Copyright (C) 2010 - 2020 Andy Green <andy@warmcat.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*
* The generic wifi netdevs follow a
*/
#include "private-lib-core.h"
int
lws_netdev_wifi_rssi_sort_compare(const lws_dll2_t *d, const lws_dll2_t *i)
{
const lws_wifi_sta_t *wsd = (const lws_wifi_sta_t *)d,
*wsi = (const lws_wifi_sta_t *)i;
return rssi_averaged(wsd) > rssi_averaged(wsi);
}
void
lws_netdev_wifi_scan_empty(lws_netdev_instance_wifi_t *wnd)
{
lws_start_foreach_dll_safe(struct lws_dll2 *, p, p1, lws_dll2_get_head(
&wnd->scan)) {
lws_wifi_sta_t *s = lws_container_of(p, lws_wifi_sta_t, list);
lws_dll2_remove(p);
lws_free(s);
} lws_end_foreach_dll_safe(p, p1);
}
void
lws_netdev_wifi_scan(lws_sorted_usec_list_t *sul)
{
lws_netdev_instance_wifi_t *wnd = lws_container_of(sul,
lws_netdev_instance_wifi_t, sul_scan);
wnd->inst.ops->scan(&wnd->inst);
}
lws_wifi_sta_t *
lws_netdev_wifi_scan_find(lws_netdev_instance_wifi_t *wnd, const char *ssid,
const uint8_t *bssid)
{
lws_start_foreach_dll(struct lws_dll2 *, p, lws_dll2_get_head(
&wnd->scan)) {
lws_wifi_sta_t *w = lws_container_of(p, lws_wifi_sta_t, list);
if (!strcmp(ssid, (const char *)&w[1]) &&
!memcmp(bssid, w->bssid, 6))
return w;
} lws_end_foreach_dll(p);
return NULL;
}
int
lws_netdev_wifi_scan_select(lws_netdev_instance_wifi_t *wnd)
{
lws_netdevs_t *netdevs = lws_netdevs_from_ndi(&wnd->inst);
struct lws_context *cx = lws_context_from_netdevs(netdevs);
uint32_t least_recent = 0xffffffff;
lws_wifi_creds_t *pc = NULL;
lws_wifi_sta_t *pw = NULL;
/*
* Trim enough of the lowest RSSI guys in order to get us below the
* limit we are allowed to keep track of...
*/
while (wnd->scan.count > LWS_WIFI_MAX_SCAN_TRACK) {
struct lws_dll2 *p = lws_dll2_get_tail(&wnd->scan);
lws_wifi_sta_t *w = lws_container_of(p, lws_wifi_sta_t, list);
lws_dll2_remove(p);
lws_free(w);
}
/*
* ... let's dump what's left
*/
lws_start_foreach_dll(struct lws_dll2 *, p, lws_dll2_get_head(
&wnd->scan)) {
lws_wifi_sta_t *w = lws_container_of(p, lws_wifi_sta_t, list);
lwsl_notice("%s: %s, %02X:%02X:%02X:%02X:%02X:%02X, ch %d, rssi %d\n",
__func__, (const char *)&w[1], w->bssid[0],
w->bssid[1], w->bssid[2], w->bssid[3], w->bssid[4],
w->bssid[5], w->ch, rssi_averaged(w));
} lws_end_foreach_dll(p);
/*
* make sure we have our device's connection credentials at hand
*/
if (!netdevs->ac_creds &&
lws_netdev_credentials_settings_get(netdevs))
return 0;
netdevs->refcount_creds++;
/*
* Let's go through each starting from the best RSSI seeing if we
* have credentials... if we do, pick the one we least-recently tried
*/
lws_start_foreach_dll(struct lws_dll2 *, p1, wnd->scan.head) {
lws_wifi_sta_t *w = lws_container_of(p1, lws_wifi_sta_t, list);
lws_start_foreach_dll(struct lws_dll2 *, q,
netdevs->owner_creds.head) {
lws_wifi_creds_t *c = lws_container_of(q,
lws_wifi_creds_t,
list);
if (!strcmp((const char *)&w[1], c->ssid) &&
w->last_seen < least_recent) {
/*
* Not <= so we stick with higher RSSI when
* all 0
*/
pc = c;
pw = w;
least_recent = w->last_seen;
}
} lws_end_foreach_dll(q);
} lws_end_foreach_dll(p1);
if (least_recent != 0xffffffff) {
/*
* We picked one to try... note what we're trying so we can
* record it in settings as last successful
*/
lws_strncpy(wnd->current_attempt_ssid, (const char *)&pw[1],
sizeof(wnd->current_attempt_ssid));
memcpy(wnd->current_attempt_bssid, pw->bssid, LWS_ETH_ALEN);
wnd->inst.ops->connect(&wnd->inst, pc->ssid, pc->passphrase,
pw->bssid);
} else {
/*
* We couldn't see anyone we recognized on this scan, let's
* rescan in a bit
*/
lwsl_notice("%s: nothing usable in scan, redoing in 3s\n", __func__);
lws_sul_schedule(cx, 0, &wnd->sul_scan, lws_netdev_wifi_scan,
3 * LWS_US_PER_SEC);
}
if (!--netdevs->refcount_creds) {
lws_dll2_owner_clear(&netdevs->owner_creds);
lwsac_free(&netdevs->ac_creds);
}
return 0;
}
/*
* Initially our best bet is just try to reconnect to whatever we last
* succeeded to connect to
*/
int
lws_netdev_wifi_redo_last(lws_netdev_instance_wifi_t *wnd)
{
lws_netdevs_t *netdevs = lws_netdevs_from_ndi(&wnd->inst);
uint8_t buf[256], bssid[LWS_ETH_ALEN];
const char *ssid, *pp = "", *pb;
char setname[16], ssid_copy[33];
size_t l = sizeof(buf), al;
lws_wifi_creds_t *cred;
/*
* Let's try to retreive the last successful connect info for this
* netdev
*/
lws_snprintf(setname, sizeof(setname), "netdev.last.%s", wnd->inst.name);
if (lws_settings_plat_get(netdevs->si, setname, buf, &l))
return 1;
lwsl_notice("%s: last successful %s\n", __func__, buf);
ssid = lws_json_simple_find((const char *)buf, l, "\"ssid\":", &al);
if (!ssid || al > 32)
return 1;
memcpy(ssid_copy, ssid, al);
ssid_copy[al + 1] = '\0';
pb = lws_json_simple_find((const char *)buf, l, "\"bssid\":", &al);
if (!pb)
return 1;
lws_hex_to_byte_array(pb, bssid, sizeof(bssid));
/*
* make sure we have our device's connection credentials at hand
*/
if (!netdevs->ac_creds &&
lws_netdev_credentials_settings_get(netdevs))
return 1;
netdevs->refcount_creds++;
cred = lws_netdev_credentials_find(netdevs, ssid_copy, bssid);
if (cred)
pp = cred->passphrase;
lws_strncpy(wnd->current_attempt_ssid, ssid_copy,
sizeof(wnd->current_attempt_ssid));
memcpy(wnd->current_attempt_bssid, bssid, LWS_ETH_ALEN);
wnd->inst.ops->connect(&wnd->inst, ssid_copy, pp, bssid);
if (!--netdevs->refcount_creds) {
lws_dll2_owner_clear(&netdevs->owner_creds);
lwsac_free(&netdevs->ac_creds);
}
return 0;
}