Allow forced pairing and removing of bonds

A much requested feature to work around hosts aggressively connecting to gamepad unwantedly.

Example provided

Author: lemmingDev

BleConnectionStatus.cpp

@@ -1,4 +1,5 @@
 #include "BleConnectionStatus.h"
+#include <NimBLEDevice.h>
 
 BleConnectionStatus::BleConnectionStatus(void)
 {
@@ -7,14 +8,28 @@ BleConnectionStatus::BleConnectionStatus(void)
 void BleConnectionStatus::onConnect(NimBLEServer *pServer, NimBLEConnInfo& connInfo)
 {
     pServer->updateConnParams(connInfo.getConnHandle(), 6, 7, 0, 600);
+	
+	//NimBLEAddress addr = connInfo.getAddress();
+    //Serial.print("onConnect - Connected from: ");
+    //Serial.println(addr.toString().c_str());
 }
 
 void BleConnectionStatus::onDisconnect(NimBLEServer* pServer, NimBLEConnInfo& connInfo, int reason)
 {
+	//NimBLEAddress addr = connInfo.getAddress();
+    //Serial.print("onDisconnect - Disconnected from: ");
+    //Serial.println(addr.toString().c_str());
+	
     this->connected = false;
+	delay(500);
+	NimBLEDevice::startAdvertising();  // Restart advertising
 }
 
 void BleConnectionStatus::onAuthenticationComplete(NimBLEConnInfo& connInfo)
 {
+	//NimBLEAddress addr = connInfo.getAddress();
+    //Serial.print("onAuthenticationComplete - Connected from: ");
+    //Serial.println(addr.toString().c_str());
+	
     this->connected = true;
 }

BleGamepad.cpp

@@ -1399,30 +1399,129 @@ void BleGamepad::setBatteryLevel(uint8_t level)
     }
 }
 
-bool BleGamepad::isOutputReceived(){
-    if(enableOutputReport && outputReceiver){
-        if(this->outputReceiver->outputFlag){
+bool BleGamepad::isOutputReceived()
+{
+    if(enableOutputReport && outputReceiver)
+	{
+        if(this->outputReceiver->outputFlag)
+		{
             this->outputReceiver->outputFlag=false; // Clear Flag
             return true;
         }
     }
     return false;
 }
-uint8_t* BleGamepad::getOutputBuffer(){
-    if(enableOutputReport && outputReceiver){
+
+uint8_t* BleGamepad::getOutputBuffer()
+{
+    if(enableOutputReport && outputReceiver)
+	{
         memcpy(outputBackupBuffer, outputReceiver->outputBuffer, outputReportLength); // Creating a backup to avoid buffer being overwritten while processing data
         return outputBackupBuffer;
     }
     return nullptr;
 }
+
+bool BleGamepad::deleteAllBonds(bool resetBoard)
+{
+	bool success = false;
+	
+	NimBLEDevice::deleteAllBonds();
+	success = true;
+	delay(500);
+		
+	if (resetBoard)
+	{
+	    ESP.restart();
+	}
+ 
+	return success;	// Returns false if all bonds are not deleted
+}
+
+bool BleGamepad::deleteBond(bool resetBoard)
+{
+	bool success = false;
+	
+	NimBLEServer* server = NimBLEDevice::getServer();
+	
+    if (server) 
+	{
+		NimBLEConnInfo info = server->getPeerInfo(0);
+		NimBLEAddress address = info.getAddress();
+		
+		success = NimBLEDevice::deleteBond(address);	
+
+		delay(500);
+		
+		if (resetBoard)
+		{
+		    ESP.restart();
+		}
+    } 
+	return success;	// Returns false if current bond is not deleted
+}
+
+bool BleGamepad::enterPairingMode()
+{
+	NimBLEServer* server = NimBLEDevice::getServer();
+	
+    if (server) 
+	{
+		//Serial.println("Entered pairing mode");
+		
+		// Get current connection information and address
+		NimBLEConnInfo currentConnInfo = server->getPeerInfo(0);
+		NimBLEAddress currentAddress = currentConnInfo.getAddress();
+		//Serial.print("Current Address is: ");
+		//Serial.println(currentAddress.toString().c_str());
+		
+		// Disconnect from current connection
+		for (uint16_t connHandle : server->getPeerDevices()) 
+		{
+            server->disconnect(connHandle); // Disconnect the client
+			//Serial.println("Disconnected from client");
+			delay(1000);
+        }
+		
+		bool connectedToOldDevice = true;
+		
+		// While connected to old device, keep allowing to connect new new devices
+		while(connectedToOldDevice)
+		{
+			//Serial.println("While loop entered");
+			delay(10);	// Needs a delay to work - do not remove!
+			
+			if(this->isConnected())
+			{
+			    NimBLEConnInfo newConnInfo = server->getPeerInfo(0);
+		        NimBLEAddress newAddress = newConnInfo.getAddress();
+		
+				//Serial.print("Current Address is: ");
+		        //Serial.println(newAddress.toString().c_str());
+		
+			    // Block specific MAC address
+		        if (newAddress == currentAddress) 
+		        {
+					//Serial.println("Addresses match - blocking");
+			        server->disconnect(newConnInfo.getConnHandle());
+					delay(500);
+		        }
+				else
+				{
+					//Serial.println("New device connected");
+					connectedToOldDevice = false;
+					return true;
+				}
+			}
+		}
+		return false; // Might want to adjust this function to stay in pairing mode for a while, and then return false after a while if no other device pairs with it
+    }
+}
+
+
 void BleGamepad::taskServer(void *pvParameter)
 {
     BleGamepad *BleGamepadInstance = (BleGamepad *)pvParameter; // static_cast<BleGamepad *>(pvParameter);
-
-    // Use the procedure below to set a custom Bluetooth MAC address
-    // Compiler adds 0x02 to the last value of board's base MAC address to get the BT MAC address, so take 0x02 away from the value you actually want when setting
-    //uint8_t newMACAddress[] = {0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF - 0x02};
-    //esp_base_mac_addr_set(&newMACAddress[0]); // Set new MAC address 
 
     NimBLEDevice::init(BleGamepadInstance->deviceName);
     NimBLEServer *pServer = NimBLEDevice::createServer();

BleGamepad.h

@@ -113,6 +113,9 @@ class BleGamepad
     std::string deviceName;
     bool isOutputReceived();
     uint8_t* getOutputBuffer();
+	bool deleteBond(bool resetBoard = false);
+	bool deleteAllBonds(bool resetBoard = false);
+	bool enterPairingMode();
 
 protected:
     virtual void onStarted(NimBLEServer *pServer){};

examples/ForcePairingMode/ForcePairingMode.ino

@@ -0,0 +1,67 @@
+/*
+ * A simple sketch that, upon a button press, disconnects from an aggressive client 
+ * until a new client connects to the gamepad
+ * 
+ * If it finds another client that's already paired, it will connect to that
+ * 
+ * If it doesn't find another paired device, it will allow you to pair a new one
+ * 
+ * If you want a more permanent solution, instead use bleGamepad.deleteBond() 
+ * which will delete the bond for the currently connected client and allow other
+ * clients to connect to it
+ * 
+ * Use bleGamepad.deletAllBonds() to delete all bonds from the gamepad
+ * 
+ * After deleting bonds, it is best to unpair them from the client device such
+ * as your phone or PC otherwise the gamepad may briefly connect while searching
+ *
+ * The deleteBond and deletAllBonds functions can optionalayy reset the gamepad with
+ * deletAllBonds(true) or deleteBond(true), although it shouldn't be needed
+ * as the advertising should now start again after a client is disconnected
+ * 
+ * They all return a boolean for success or failure if wanted
+ */
+
+#include <Arduino.h>
+#include <BleGamepad.h> // https://github.com/lemmingDev/ESP32-BLE-Gamepad
+
+#define DISCONNECTPIN 0 // Pin disconnect button is attached to
+
+BleGamepad bleGamepad;
+
+void setup()
+{
+    Serial.begin(115200);
+    pinMode(DISCONNECTPIN, INPUT_PULLUP);
+    bleGamepad.begin();
+}
+
+void loop()
+{
+    if (bleGamepad.isConnected())
+    {
+        // Enter forced pairing mode 
+        // It repeatedly disconnects from currently connected device until a new device is paired
+        // Returns true if a new device is connected
+        // For now, enters an endless loop if no new device found
+        // Simply reset device to have it revert to previous behaviour
+        if (digitalRead(DISCONNECTPIN) == LOW) // On my board, pin 0 is LOW for pressed
+        {   
+            bool pairingResult = bleGamepad.enterPairingMode();
+
+            if(pairingResult)
+            {
+              Serial.println("New device paired successfully"); 
+            }
+            else
+            {
+              Serial.println("No new device paired");
+            }
+        }
+    }
+    else
+    {
+        Serial.println("No device connected");
+        delay(1000);
+    }
+}