central auto removes failed bond keys

Author: hathach

libraries/Bluefruit52Lib/src/BLECentral.cpp

@@ -142,8 +142,8 @@ void BLECentral::_eventHandler(ble_evt_t* evt)
     case BLE_GAP_EVT_CONNECTED:
     {
       // Try to secure connection if we bonded previously
-      static bond_keys_t ltkey;
-      if ( conn->loadLongTermKey(&ltkey) )
+      bond_keys_t ltkey;
+      if ( conn->loadBondKey(&ltkey) )
       {
         BLEPairing* secure = &Bluefruit.Pairing;
         secure->_encrypt(conn_hdl, &ltkey);
@@ -154,6 +154,15 @@ void BLECentral::_eventHandler(ble_evt_t* evt)
     case BLE_GAP_EVT_DISCONNECTED:
     break;
 
+    case BLE_GAP_EVT_CONN_SEC_UPDATE:
+      if ( conn->bonded() && !conn->secured() )
+      {
+        // Bonded but failed to secure connection
+        // Peer must have removed LTKey, we should remove ours as well
+        conn->removeBondKey();
+      }
+    break;
+
     case BLE_GAP_EVT_CONN_PARAM_UPDATE_REQUEST:
     {
       // Peripheral request to change connection parameter

libraries/Bluefruit52Lib/src/BLEConnection.cpp

@@ -258,6 +258,13 @@ bool BLEConnection::loadBondKey(bond_keys_t* ltkey)
   return true;
 }
 
+bool BLEConnection::removeBondKey(void)
+{
+  VERIFY(_bonded);
+  bond_remove_key(_role, &_bond_id_addr);
+  return true;
+}
+
 bool BLEConnection::requestPairing(void)
 {
   // skip if already paired

libraries/Bluefruit52Lib/src/utility/bonding.cpp

@@ -356,4 +356,6 @@ void bond_remove_key(uint8_t role, ble_gap_addr_t const* id_addr)
   get_fname(filename, role, id_addr->addr);
 
   InternalFS.remove(filename);
+
+  BOND_LOG("Removed keys from file %s", filename);
 }