Add support for hidden networks in WiFiMulti (espressif#9202)

* Add support for hidden networks in WiFiMulti * Update WiFiMulti.cpp * Update WiFiMulti.cpp

Author: lucasssvaz

libraries/WiFi/src/WiFiMulti.cpp

@@ -90,9 +90,10 @@ bool WiFiMulti::addAP(const char* ssid, const char *passphrase)
  return true;
 }
 
-uint8_t WiFiMulti::run(uint32_t connectTimeout)
+uint8_t WiFiMulti::run(uint32_t connectTimeout, bool scanHidden)
 {
  int8_t scanResult;
+ unsigned long startTime;
  uint8_t status = WiFi.status();
  if(status == WL_CONNECTED) {
  if (!_bWFMInit && _connectionTestCBFunc != NULL){
@@ -116,13 +117,13 @@ uint8_t WiFiMulti::run(uint32_t connectTimeout)
  status = WiFi.status();
  }
 
- scanResult = WiFi.scanNetworks();
+ scanResult = WiFi.scanNetworks(false, scanHidden);
  if (scanResult == WIFI_SCAN_RUNNING) {
  // scan is running
  return WL_NO_SSID_AVAIL;
  } else if (scanResult >= 0) {
  // scan done analyze
- int32_t bestIndex = 0;
+ int32_t bestIndex = -1;
  WifiAPlist_t bestNetwork { NULL, NULL, false };
  int bestNetworkDb = INT_MIN;
  int bestNetworkSec = WIFI_AUTH_MAX;
@@ -145,8 +146,10 @@ uint8_t WiFiMulti::run(uint32_t connectTimeout)
  uint8_t sec_scan;
  uint8_t* BSSID_scan;
  int32_t chan_scan;
+ bool hidden_scan;
 
  WiFi.getNetworkInfo(i, ssid_scan, sec_scan, rssi_scan, BSSID_scan, chan_scan);
+ hidden_scan = (ssid_scan.length() == 0) && scanHidden;
  // add any Open WiFi AP to the list, if allowed with setAllowOpenAP(true)
  if (_bAllowOpenAP && sec_scan == WIFI_AUTH_OPEN){
  bool found = false;
@@ -163,14 +166,49 @@ uint8_t WiFiMulti::run(uint32_t connectTimeout)
  }
  }
 
+ if (hidden_scan) {
+ log_v("hidden ssid on channel %d found, trying to connect with known credentials...", chan_scan);
+ }
+
  bool known = false;
  for(uint32_t x = 0; x < APlist.size(); x++) {
  WifiAPlist_t entry = APlist[x];
 
- if(ssid_scan == entry.ssid) { // SSID match
- log_v("known ssid: %s, has failed: %s", entry.ssid, entry.hasFailed ? "yes" : "no");
- foundCount++;
- if (!entry.hasFailed){
+ if(ssid_scan == entry.ssid || hidden_scan) { // SSID match or hidden network found
+ if (!hidden_scan) {
+ log_v("known ssid: %s, has failed: %s", entry.ssid, entry.hasFailed ? "yes" : "no");
+ foundCount++;
+ }
+ if (!entry.hasFailed) {
+ if (hidden_scan) {
+ WiFi.begin(entry.ssid, entry.passphrase, chan_scan, BSSID_scan);
+
+ // If the ssid returned from the scan is empty, it is a hidden SSID
+ // it appears that the WiFi.begin() function is asynchronous and takes
+ // additional time to connect to a hidden SSID. Therefore a delay of 1000ms
+ // is added for hidden SSIDs before calling WiFi.status()
+ delay(1000);
+
+ status = WiFi.status();
+ startTime = millis();
+
+ while (status != WL_CONNECTED && (millis() - startTime) <= connectTimeout)
+ {
+ delay(10);
+ status = WiFi.status();
+ }
+
+ WiFi.disconnect();
+ delay(10);
+
+ if (status == WL_CONNECTED) {
+ log_v("hidden ssid %s found", entry.ssid);
+ ssid_scan = entry.ssid;
+ foundCount++;
+ } else {
+ continue;
+ }
+ }
  known = true;
  log_v("rssi_scan: %d, bestNetworkDb: %d", rssi_scan, bestNetworkDb);
  if(rssi_scan > bestNetworkDb) { // best network
@@ -191,10 +229,24 @@ uint8_t WiFiMulti::run(uint32_t connectTimeout)
  }
  }
 
- if(known) {
- log_d(" ---> %d: [%d][%02X:%02X:%02X:%02X:%02X:%02X] %s (%d) %c", i, chan_scan, BSSID_scan[0], BSSID_scan[1], BSSID_scan[2], BSSID_scan[3], BSSID_scan[4], BSSID_scan[5], ssid_scan.c_str(), rssi_scan, (sec_scan == WIFI_AUTH_OPEN) ? ' ' : '*');
+ if (known) {
+ log_d(" ---> %d: [%d][%02X:%02X:%02X:%02X:%02X:%02X] %s (%d) (%c) (%s)",
+ i,
+ chan_scan,
+ BSSID_scan[0], BSSID_scan[1], BSSID_scan[2], BSSID_scan[3], BSSID_scan[4], BSSID_scan[5],
+ ssid_scan.c_str(),
+ rssi_scan,
+ (sec_scan == WIFI_AUTH_OPEN) ? ' ' : '*',
+ (hidden_scan) ? "hidden" : "visible");
  } else {
- log_d(" %d: [%d][%02X:%02X:%02X:%02X:%02X:%02X] %s (%d) %c", i, chan_scan, BSSID_scan[0], BSSID_scan[1], BSSID_scan[2], BSSID_scan[3], BSSID_scan[4], BSSID_scan[5], ssid_scan.c_str(), rssi_scan, (sec_scan == WIFI_AUTH_OPEN) ? ' ' : '*');
+ log_d(" %d: [%d][%02X:%02X:%02X:%02X:%02X:%02X] %s (%d) (%c) (%s)",
+ i,
+ chan_scan,
+ BSSID_scan[0], BSSID_scan[1], BSSID_scan[2], BSSID_scan[3], BSSID_scan[4], BSSID_scan[5],
+ ssid_scan.c_str(),
+ rssi_scan,
+ (sec_scan == WIFI_AUTH_OPEN) ? ' ' : '*',
+ (hidden_scan) ? "hidden" : "visible");
  }
  }
  log_v("foundCount = %d, failCount = %d", foundCount, failCount);
@@ -206,7 +258,7 @@ uint8_t WiFiMulti::run(uint32_t connectTimeout)
  // clean up ram
  WiFi.scanDelete();
 
- if(bestNetwork.ssid) {
+ if(bestIndex >= 0) {
  log_i("[WIFI] Connecting BSSID: %02X:%02X:%02X:%02X:%02X:%02X SSID: %s Channel: %d (%d)", bestBSSID[0], bestBSSID[1], bestBSSID[2], bestBSSID[3], bestBSSID[4], bestBSSID[5], bestNetwork.ssid, bestChannel, bestNetworkDb);
 
  if (ipv6_support == true) {
@@ -218,7 +270,7 @@ uint8_t WiFiMulti::run(uint32_t connectTimeout)
  status = WiFi.status();
  _bWFMInit = true;
 
- auto startTime = millis();
+ startTime = millis();
  // wait for connection, fail, or timeout
  while(status != WL_CONNECTED && (millis() - startTime) <= connectTimeout) { // && status != WL_NO_SSID_AVAIL && status != WL_CONNECT_FAILED
  delay(10);

libraries/WiFi/src/WiFiMulti.h

@@ -44,7 +44,7 @@ class WiFiMulti
  ~WiFiMulti();
 
  bool addAP(const char* ssid, const char *passphrase = NULL);
- uint8_t run(uint32_t connectTimeout=5000);
+ uint8_t run(uint32_t connectTimeout=5000, bool scanHidden=false);
  void enableIPv6(bool state);
 
  // Force (default: true) to only keep connected or to connect to an AP from the provided WiFiMulti list.