Only one SSID per device

[Bigfoot491993]

Hi, whenever I run this script it only gives me one remembered SSID per device, this is a different SSID than that device is currently connected to, so it really is a saved network, however I don't know how to get more SSID's out of it. I read somewhere that Espressif limited the montioring mode in recent releases, any idea how to fix this? (I programmed it using the Arduino IDE)

[alafanechere]

Hello @Bigfoot491993 , from my understanding, each probe request contains one SSID. If the device wants to check presence of multiple ssids around it will send multiple probe requests.

[Bigfoot491993]

Interesting, I'll test it again as soon as possible but I don't think I ever saw an other SSID for a given MAC over the course of 15 minutes. I read somewhere that esperrif limited the firmware in recent versions but I haven't managed to get an older version working with the Arduino IDE.

[iCounterBOX]

Hi @Bigfoot491993 ,
i loop the 14 Channels ( usual channel hopping ). a struct array store the detected devices ( MAC is unique ! ).. The ssid will get concatinated..within this 14 channel hop we receive several ssid string ( if they occure..)
here some sniplet from a longer code:

// A Struct Array to keep the sniffed MAC devices

typedef struct  {								
	char deviceMacAddr[18];						//  peerMac
	char  ssid[100];								// Some will have ssid ..some not....less memory MAX flexibility - https://hackingmajenkoblog.wordpress.com/2016/02/04/the-evils-of-arduino-strings/
	uint8 wifiChannel;							// Channel
	signed int rssi = 0;						// RSSI		
} deviceRecordType;
#define MACdeviceDataMAXelements  200
deviceRecordType  MACdeviceData[MACdeviceDataMAXelements];		// instead of EDB we try hier a STRUCT ARRAY
int MACdeviceDataIndex = 0;	    // Index of this Struct Array

I limt the ssid! ( limitation in stack .. heap ).
I adapted the showMetadata() to collect my data in this struct:

static void showMetadata(struct SnifferPacket* snifferPacket)
{
	unsigned int frameControl = ((unsigned int)snifferPacket->data[1] << 8) + snifferPacket->data[0];
	// uint8_t version      = (frameControl & 0b0000000000000011) >> 0;
	uint8_t frameType = (frameControl & 0b0000000000001100) >> 2;
	uint8_t frameSubType = (frameControl & 0b0000000011110000) >> 4;
	// uint8_t toDS         = (frameControl & 0b0000000100000000) >> 8;
	// uint8_t fromDS       = (frameControl & 0b0000001000000000) >> 9;
	// Only look for probe request packets
	if (frameType != TYPE_MANAGEMENT || frameSubType != SUBTYPE_PROBE_REQUEST)
	{
		//Serial.println("showMetadata() - bedingung nicht erfüllt: frameType != TYPE_MANAGEMENT || frameSubType != SUBTYPE_PROBE_REQUEST --- RETURN ");
		return;
	}
	// Blink the LED / pro gültigem ChannelHop und gefundenem Wert!!
	digitalWrite(LED_BLUE_MCU, ledStatus); // Write LED high/low
	ledStatus = (ledStatus == HIGH) ? LOW : HIGH;
	currentChannel = wifi_get_channel();
	// Serial.print("showMetadata() -  current promiscuous Channel:  ");  Serial.println(currentChannel);

	// get my MAC addr - USE this to unify the Transferred Data ..MY ID !!
	String myEspMAC = WiFi.macAddress();
	//Serial.print("myEspMAC: ");
	//Serial.print(myEspMAC);
	//Serial.print(" RSSI: "); Serial.print(snifferPacket->rx_ctrl.rssi, DEC);
	//Serial.print(" Ch: ");
	//Serial.print(wifi_get_channel());
	char deviceMacAddr[] = "00:00:00:00:00:00";
	getMAC(deviceMacAddr, snifferPacket->data, 10);
	//Serial.print(" Peer MAC: ");
	//Serial.print(deviceMacAddr);
	uint8_t SSID_length = snifferPacket->data[25];
	//Serial.print(" SSID: ");
	String ssid = printDataSpan(26, SSID_length, snifferPacket->data);     	// ck: 26.11.17..die funktion macht kein serial.write jetzt mehr...wir nehmen das string ergebnis!!	
																			//concat the result into data4RestService:
	//String adrStr(deviceMacAddr);		// char array to string...is better to compare / https://stackoverflow.com/questions/8960087/how-to-convert-a-char-array-to-a-string			
		//This Device we will store Now:
		Serial.print("myEspMAC: "); Serial.print(myEspMAC);
		Serial.print(" RSSI: "); Serial.print(snifferPacket->rx_ctrl.rssi, DEC);
		Serial.print(" Ch: "); 	Serial.print(wifi_get_channel());
		Serial.print(" Peer MAC: "); Serial.print(deviceMacAddr);
		Serial.print(" SSID: "); Serial.print(ssid);
		Serial.println();
		// NEW - STRUCT DATA 
		int idx = findMACdeviceInDeviceArray(deviceMacAddr);	// FIRST we check if this MAC was Stored before within this SCAN-CYCLE ( e.g 20 SEC for 14 Cgannel ) -- Gives the Index or -1
		if (idx == -1) {		// Hurray - a NEW Wifi X-Mas-Tree
			//int nElements = sizeof MACdeviceData / sizeof MACdeviceData[0];		// ?? gab den vordefinierten wert zurück der Stuktur ?? Nicht den gerade gespeicherten Element-Count?

			if (MACdeviceDataIndex < MACdeviceDataMAXelements) {				// In MACdeviceDataMAXelements MUSS Immer der aktuelle Index stehen		
				MACdeviceData[MACdeviceDataIndex].rssi = snifferPacket->rx_ctrl.rssi;
				MACdeviceData[MACdeviceDataIndex].wifiChannel = wifi_get_channel();
				if (ssid.length() < sizeof(MACdeviceData[MACdeviceDataIndex].ssid) ) ssid.toCharArray(MACdeviceData[MACdeviceDataIndex].ssid, ssid.length() + 1);
				strncpy(MACdeviceData[MACdeviceDataIndex].deviceMacAddr, deviceMacAddr, sizeof MACdeviceData[MACdeviceDataIndex].deviceMacAddr - 1);
				//Serial.print(" INSERTed - NEW Device  in Struct-array"); Serial.println(MACdeviceData[MACdeviceDataIndex].deviceMacAddr);

				MACdeviceDataIndex += 1;
			}
			else
			{
				Serial.print(" ALERT!! - MACdeviceData / Limit Reached!!:  "); Serial.print(MACdeviceDataMAXelements);
				return;
			}			
		}
		else {														//  ***  UPDATE EXISTING WiFi DEVICE
			//Serial.print("Element Found at Position: "); Serial.println( idx + 1);
			//Serial.print("  UPDATE - MAC (or better the SSID )  in Struct-Array: "); Serial.println(deviceMacAddr);			
			//MACdeviceData[ idx].rssi = snifferPacket->rx_ctrl.rssi;			// Könnten hier zb den MittelWert eintragen?					
			if ( ssid.length() > 0 ) {													// Liegt überhaupt eine neue SSID  an?
				char *stringFound = strstr(MACdeviceData[idx].ssid, ssid.c_str());      // search for string "hassasin" in buff
				if (stringFound == NULL)												// if successful then sfound now points at ssid
				{
					ssid = ssid + ">" + MACdeviceData[idx].ssid;						//  der VORHANDENE SSID STRING wird Verlängert UM die NEUE SSID																							// Use strlen to get the length of a null-terminated string.  / sizeof returns the length of the array not the string
					const char *SSIDc = ssid.c_str();									// temp. char-String !! - https://stackoverflow.com/questions/10247212/how-concatenate-a-string-and-a-const-char
					//Serial.print(" SSID update / strlen(SSIDc): "); Serial.print(strlen(SSIDc));  Serial.print(" sizeof(MACdeviceData[MACdeviceDataIndex].ssid) : "); Serial.println(sizeof(MACdeviceData[MACdeviceDataIndex].ssid));
					if (strlen(SSIDc) < sizeof(MACdeviceData[MACdeviceDataIndex].ssid)) {
						strncpy(MACdeviceData[idx].ssid, SSIDc, strlen(SSIDc) - 1);
						//Serial.print(" UPDATED - SSID in Struct-array"); Serial.println(MACdeviceData[MACdeviceDataIndex].ssid);
					}
				}
				else
				{
					//Serial.print(" ssid.c_str() : "); Serial.print(ssid.c_str());   Serial.print(" gefunden in MACdeviceData[idx].ssid: "); Serial.println(MACdeviceData[idx].ssid);
				}
			}									
		}	
	// dataset for THIS CHANEL ist finished !!
}

findMACdeviceInDeviceArray(deviceMacAddr) is used to store ONLY unique MAC addr in our Buffer..

/*
Check if the NEW detected device is almost stored in the Array
Parameter:
peermac - the detected peerMAC of a device
nrElements = (sizeof MACdeviceData / sizeof MACdeviceData[0])		-- // https://stackoverflow.com/questions/1898657/result-of-sizeof-on-array-of-structs-in-c
return: gives the index of the peerMAC found in array
*/
int findMACdeviceInDeviceArray(char *peerMAC) {
	int nElements = MACdeviceDataIndex;
	//Serial.print("findMACdeviceInDeviceArray() nElements : ");	Serial.print(nElements); Serial.print(" MAC to search for : ");	Serial.println(peerMAC);

	for (int i = 0; i <= nElements; i++)
	{
		if (strcmp(MACdeviceData[i].deviceMacAddr, peerMAC) == 0) {					// the function returns 0 when the strings are equal			
			//Serial.print("findMACdeviceInDeviceArray() FOUND it : ");	Serial.println(MACdeviceData[i].deviceMacAddr);
			return i;
		}
	}
	return -1;
}

Now we have all data in our Buffer..can do whatever we need with it..

for (int i = 0; i < MACdeviceDataIndex; i++) {
		Serial.print("Str/myMac: "); Serial.print(WiFi.macAddress());	Serial.print(" cha: "); Serial.print(MACdeviceData[i].wifiChannel);	Serial.print(" RSSI: "); Serial.print(MACdeviceData[i].rssi);
		Serial.print(" SSID: "); Serial.print(MACdeviceData[i].ssid);	Serial.print(" MAC: "); Serial.println(MACdeviceData[i].deviceMacAddr);		
	}
	Serial.println();

[Marfbuilds]

Hey, I know its a long time ago now, but do you have the full code for this?

[kalanda]

nope