/**
* Enter pairing mode. This is mode is called to initiate pairing, and to enable FOTA programming
* of the micro:bit in cases where BLE is disabled during normal operation.
*/
void MicroBitBLEManager::pairingMode(MicroBitDisplay &display)
{
ManagedString namePrefix("BBC micro:bit [");
ManagedString namePostfix("]");
ManagedString BLEName = namePrefix + deviceName + namePostfix;
ManagedString msg("PAIRING MODE!");
int timeInPairingMode = 0;
int brightness = 255;
int fadeDirection = 0;
ble->gap().stopAdvertising();
// Clear the whitelist (if we have one), so that we're discoverable by all BLE devices.
#if CONFIG_ENABLED(MICROBIT_BLE_WHITELIST)
BLEProtocol::Address_t addresses[MICROBIT_BLE_MAXIMUM_BONDS];
Gap::Whitelist_t whitelist;
whitelist.addresses = addresses;
whitelist.capacity = MICROBIT_BLE_MAXIMUM_BONDS;
whitelist.size = 0;
ble->gap().setWhitelist(whitelist);
ble->gap().setAdvertisingPolicyMode(Gap::ADV_POLICY_IGNORE_WHITELIST);
#endif
// Update the advertised name of this micro:bit to include the device name
ble->clearAdvertisingPayload();
ble->accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED | GapAdvertisingData::LE_GENERAL_DISCOVERABLE);
ble->accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LOCAL_NAME, (uint8_t *)BLEName.toCharArray(), BLEName.length());
ble->setAdvertisingType(GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED);
ble->setAdvertisingInterval(200);
ble->gap().setAdvertisingTimeout(0);
ble->gap().startAdvertising();
// Stop any running animations on the display
display.stopAnimation();
display.scroll(msg);
// Display our name, visualised as a histogram in the display to aid identification.
showNameHistogram(display);
while(1)
{
if (pairingStatus & MICROBIT_BLE_PAIR_REQUEST)
{
timeInPairingMode = 0;
MicroBitImage arrow("0,0,255,0,0\n0,255,0,0,0\n255,255,255,255,255\n0,255,0,0,0\n0,0,255,0,0\n");
display.print(arrow,0,0,0);
if (fadeDirection == 0)
brightness -= MICROBIT_PAIRING_FADE_SPEED;
else
brightness += MICROBIT_PAIRING_FADE_SPEED;
if (brightness <= 40)
display.clear();
if (brightness <= 0)
fadeDirection = 1;
if (brightness >= 255)
fadeDirection = 0;
if (uBit.buttonA.isPressed())
{
pairingStatus &= ~MICROBIT_BLE_PAIR_REQUEST;
pairingStatus |= MICROBIT_BLE_PAIR_PASSCODE;
}
}
if (pairingStatus & MICROBIT_BLE_PAIR_PASSCODE)
{
timeInPairingMode = 0;
display.setBrightness(255);
for (int i=0; i<passKey.length(); i++)
{
display.image.print(passKey.charAt(i),0,0);
uBit.sleep(800);
display.clear();
uBit.sleep(200);
if (pairingStatus & MICROBIT_BLE_PAIR_COMPLETE)
break;
}
uBit.sleep(1000);
}
if (pairingStatus & MICROBIT_BLE_PAIR_COMPLETE)
{
if (pairingStatus & MICROBIT_BLE_PAIR_SUCCESSFUL)
{
MicroBitImage tick("0,0,0,0,0\n0,0,0,0,255\n0,0,0,255,0\n255,0,255,0,0\n0,255,0,0,0\n");
display.print(tick,0,0,0);
uBit.sleep(5000);
/*
* Disabled, as the API to return the number of active bonds is not reliable at present...
*
display.clear();
ManagedString c(getBondCount());
ManagedString c2("/");
ManagedString c3(MICROBIT_BLE_MAXIMUM_BONDS);
ManagedString c4("USED");
display.scroll(c+c2+c3+c4);
*
*
*/
}
else
{
MicroBitImage cross("255,0,0,0,255\n0,255,0,255,0\n0,0,255,0,0\n0,255,0,255,0\n255,0,0,0,255\n");
display.print(cross,0,0,0);
}
}
uBit.sleep(30);
timeInPairingMode++;
if (timeInPairingMode >= MICROBIT_BLE_PAIRING_TIMEOUT * 30)
microbit_reset();
}
}
/**
* Post constructor initialisation method as the BLE stack cannot be brought
* up in a static context.
*
* @param deviceName The name used when advertising
* @param serialNumber The serial number exposed by the device information service
* @param messageBus An instance of an EventModel, used during pairing.
* @param enableBonding If true, the security manager enabled bonding.
*
* @code
* bleManager.init(uBit.getName(), uBit.getSerial(), uBit.messageBus, true);
* @endcode
*/
void MicroBitBLEManager::init(ManagedString deviceName, ManagedString serialNumber, EventModel& messageBus, bool enableBonding)
{
ManagedString BLEName("BBC micro:bit");
this->deviceName = deviceName;
#if !(CONFIG_ENABLED(MICROBIT_BLE_WHITELIST))
ManagedString namePrefix(" [");
ManagedString namePostfix("]");
BLEName = BLEName + namePrefix + deviceName + namePostfix;
#endif
// Start the BLE stack.
#if CONFIG_ENABLED(MICROBIT_HEAP_REUSE_SD)
btle_set_gatt_table_size(MICROBIT_SD_GATT_TABLE_SIZE);
#endif
ble = new BLEDevice();
ble->init();
// automatically restart advertising after a device disconnects.
ble->gap().onDisconnection(bleDisconnectionCallback);
ble->gattServer().onSysAttrMissing(bleSysAttrMissingCallback);
// generate an event when a Bluetooth connection is established
ble->gap().onConnection(bleConnectionCallback);
// Configure the stack to hold onto the CPU during critical timing events.
// mbed-classic performs __disable_irq() calls in its timers that can cause
// MIC failures on secure BLE channels...
ble_common_opt_radio_cpu_mutex_t opt;
opt.enable = 1;
sd_ble_opt_set(BLE_COMMON_OPT_RADIO_CPU_MUTEX, (const ble_opt_t *)&opt);
#if CONFIG_ENABLED(MICROBIT_BLE_PRIVATE_ADDRESSES)
// Configure for private addresses, so kids' behaviour can't be easily tracked.
ble->gap().setAddress(BLEProtocol::AddressType::RANDOM_PRIVATE_RESOLVABLE, {0});
#endif
// Setup our security requirements.
ble->securityManager().onPasskeyDisplay(passkeyDisplayCallback);
ble->securityManager().onSecuritySetupCompleted(securitySetupCompletedCallback);
ble->securityManager().init(enableBonding, (SecurityManager::MICROBIT_BLE_SECURITY_LEVEL == SecurityManager::SECURITY_MODE_ENCRYPTION_WITH_MITM), SecurityManager::IO_CAPS_DISPLAY_ONLY);
if (enableBonding)
{
// If we're in pairing mode, review the size of the bond table.
int bonds = getBondCount();
// TODO: It would be much better to implement some sort of LRU/NFU policy here,
// but this isn't currently supported in mbed, so we'd need to layer break...
// If we're full, empty the bond table.
if (bonds >= MICROBIT_BLE_MAXIMUM_BONDS)
ble->securityManager().purgeAllBondingState();
}
#if CONFIG_ENABLED(MICROBIT_BLE_WHITELIST)
// Configure a whitelist to filter all connection requetss from unbonded devices.
// Most BLE stacks only permit one connection at a time, so this prevents denial of service attacks.
BLEProtocol::Address_t bondedAddresses[MICROBIT_BLE_MAXIMUM_BONDS];
Gap::Whitelist_t whitelist;
whitelist.addresses = bondedAddresses;
whitelist.capacity = MICROBIT_BLE_MAXIMUM_BONDS;
ble->securityManager().getAddressesFromBondTable(whitelist);
ble->gap().setWhitelist(whitelist);
ble->gap().setScanningPolicyMode(Gap::SCAN_POLICY_IGNORE_WHITELIST);
ble->gap().setAdvertisingPolicyMode(Gap::ADV_POLICY_FILTER_CONN_REQS);
#endif
// Configure the radio at our default power level
setTransmitPower(MICROBIT_BLE_DEFAULT_TX_POWER);
// Bring up core BLE services.
#if CONFIG_ENABLED(MICROBIT_BLE_DFU_SERVICE)
new MicroBitDFUService(*ble);
#endif
#if CONFIG_ENABLED(MICROBIT_BLE_DEVICE_INFORMATION_SERVICE)
DeviceInformationService ble_device_information_service (*ble, MICROBIT_BLE_MANUFACTURER, MICROBIT_BLE_MODEL, serialNumber.toCharArray(), MICROBIT_BLE_HARDWARE_VERSION, MICROBIT_BLE_FIRMWARE_VERSION, MICROBIT_BLE_SOFTWARE_VERSION);
#endif
#if CONFIG_ENABLED(MICROBIT_BLE_EVENT_SERVICE)
new MicroBitEventService(*ble, messageBus);
#else
(void)messageBus;
#endif
// Configure for high speed mode where possible.
Gap::ConnectionParams_t fast;
ble->getPreferredConnectionParams(&fast);
fast.minConnectionInterval = 8; // 10 ms
fast.maxConnectionInterval = 16; // 20 ms
fast.slaveLatency = 0;
ble->setPreferredConnectionParams(&fast);
// Setup advertising.
#if CONFIG_ENABLED(MICROBIT_BLE_WHITELIST)
ble->accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED);
#else
ble->accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED | GapAdvertisingData::LE_GENERAL_DISCOVERABLE);
#endif
ble->accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LOCAL_NAME, (uint8_t *)BLEName.toCharArray(), BLEName.length());
ble->setAdvertisingType(GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED);
ble->setAdvertisingInterval(200);
#if (MICROBIT_BLE_ADVERTISING_TIMEOUT > 0)
ble->gap().setAdvertisingTimeout(MICROBIT_BLE_ADVERTISING_TIMEOUT);
#endif
// If we have whitelisting enabled, then prevent only enable advertising of we have any binded devices...
// This is to further protect kids' privacy. If no-one initiates BLE, then the device is unreachable.
// If whiltelisting is disabled, then we always advertise.
#if CONFIG_ENABLED(MICROBIT_BLE_WHITELIST)
if (whitelist.size > 0)
#endif
ble->startAdvertising();
}
