Schoumi
/
microbit-dal
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
microbit-dal/source/ble-services/MicroBitBLEManager.cpp

473 lines
15 KiB
C++
Raw Blame History

#include "MicroBit.h"
/* The underlying Nordic libraries that support BLE do not compile cleanly with the stringent GCC settings we employ
* If we're compiling under GCC, then we suppress any warnings generated from this code (but not the rest of the DAL)
* The ARM cc compiler is more tolerant. We don't test __GNUC__ here to detect GCC as ARMCC also typically sets this
* as a compatability option, but does not support the options used...
*/
#if !defined(__arm)
#pragma GCC diagnostic ignored "-Wunused-function"
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wunused-parameter"
#endif
#include "ble.h"
/*
* Return to our predefined compiler settings.
*/
#if !defined(__arm)
#pragma GCC diagnostic pop
#endif
#define MICROBIT_PAIRING_FADE_SPEED 4
const char* MICROBIT_BLE_MANUFACTURER = NULL;
const char* MICROBIT_BLE_MODEL = "BBC micro:bit";
const char* MICROBIT_BLE_HARDWARE_VERSION = NULL;
const char* MICROBIT_BLE_FIRMWARE_VERSION = MICROBIT_DAL_VERSION;
const char* MICROBIT_BLE_SOFTWARE_VERSION = NULL;
const int8_t MICROBIT_BLE_POWER_LEVEL[] = {-30, -20, -16, -12, -8, -4, 0, 4};
/*
* Many of the mbed interfaces we need to use only support callbacks to plain C functions, rather than C++ methods.
* So, we maintain a pointer to the MicroBitBLEManager that's in use. Ths way, we can still access resources on the micro:bit
* whilst keeping the code modular.
*/
static MicroBitBLEManager *manager = NULL;
/**
* Callback when a BLE GATT disconnect occurs.
*/
static void bleDisconnectionCallback(const Gap::DisconnectionCallbackParams_t *reason)
{
(void) reason; /* -Wunused-param */
// configure the stack to release CPU during critical timing events.
// mbed-classic performs __disabe_irq calls in its timers, which can cause MIC failures
// on secure BLE channels.
ble_common_opt_radio_cpu_mutex_t opt;
opt.enable = 0;
sd_ble_opt_set(BLE_COMMON_OPT_RADIO_CPU_MUTEX, (const ble_opt_t *)&opt);
if (manager)
manager->advertise();
}
/**
* Callback when a BLE GATT connect occurs.
*/
static void bleConnectionCallback(const Gap::ConnectionCallbackParams_t *reason)
{
// configure the stack to hold on to CPU during critical timing events.
// mbed-classic performs __disabe_irq calls in its timers, which 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);
// Ensure that there's no stale, cached information in the client... invalidate all characteristics.
uint16_t len = 8;
// Configure the ServiceChanged characteristic to receive service changed indications
// TODO: This is really a workaround as we can't maintain persistent state on the micro:bit across USB
// reprogramming flashes.... yet.
uint8_t data[] = {0x0B,0x00,0x02,0x00,0x02,0x00,0xB8,0x46};
sd_ble_gatts_sys_attr_set(reason->handle, data, len, BLE_GATTS_SYS_ATTR_FLAG_SYS_SRVCS);
sd_ble_gatts_service_changed(reason->handle, 0x000c, 0xffff);
}
static void passkeyDisplayCallback(Gap::Handle_t handle, const SecurityManager::Passkey_t passkey)
{
(void) handle; /* -Wunused-param */
ManagedString passKey((const char *)passkey, SecurityManager::PASSKEY_LEN);
if (manager)
manager->pairingRequested(passKey);
}
static void securitySetupCompletedCallback(Gap::Handle_t handle, SecurityManager::SecurityCompletionStatus_t status)
{
(void) handle; /* -Wunused-param */
if (manager)
manager->pairingComplete(status == SecurityManager::SEC_STATUS_SUCCESS);
}
/**
* Constructor.
*
* Configure and manage the micro:bit's Bluetooth Low Energy (BLE) stack.
* Note that the BLE stack *cannot* be brought up in a static context.
* (the software simply hangs or corrupts itself).
* Hence, we bring it up in an explicit init() method, rather than in the constructor.
*/
MicroBitBLEManager::MicroBitBLEManager()
{
manager = this;
this->ble = NULL;
this->pairingStatus = 0;
}
/**
* Makes the micro:bit discoverable via BLE, such that bonded devices can connect
* When called, the micro:bit will begin advertising for a predefined period, thereby allowing
* bonded devices to connect.
*/
void MicroBitBLEManager::advertise()
{
if(ble)
ble->gap().startAdvertising();
}
/**
* Post constructor initialisation method.
* After *MUCH* pain, it's noted that the BLE stack can't be brought up in a
* static context, so we bring it up here rather than in the constructor.
* n.b. This method *must* be called in main() or later, not before.
*
* Example:
* @code
* uBit.init();
* @endcode
*/
void MicroBitBLEManager::init(ManagedString deviceName, ManagedString serialNumber, bool enableBonding)
{
ManagedString BLEName("BBC micro:bit");
this->deviceName = deviceName;
// Start the BLE stack.
ble = new BLEDevice();
ble->init();
// automatically restart advertising after a device disconnects.
ble->onDisconnection(bleDisconnectionCallback);
ble->onConnection(bleConnectionCallback);
#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, MICROBIT_BLE_REQUIRE_MITM, SecurityManager::IO_CAPS_DISPLAY_ONLY);
// If we're in pairing mode, review the size of the bond table.
if (enableBonding)
{
// 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...
int bonds = getBondCount();
// 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 any configured auxiliary 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);
#endif
#if CONFIG_ENABLED(MICROBIT_BLE_LED_SERVICE)
new MicroBitLEDService(*ble);
#endif
#if CONFIG_ENABLED(MICROBIT_BLE_ACCELEROMETER_SERVICE)
new MicroBitAccelerometerService(*ble);
#endif
#if CONFIG_ENABLED(MICROBIT_BLE_MAGNETOMETER_SERVICE)
new MicroBitMagnetometerService(*ble);
#endif
#if CONFIG_ENABLED(MICROBIT_BLE_BUTTON_SERVICE)
new MicroBitButtonService(*ble);
#endif
#if CONFIG_ENABLED(MICROBIT_BLE_IO_PIN_SERVICE)
new MicroBitIOPinService(*ble);
#endif
#if CONFIG_ENABLED(MICROBIT_BLE_TEMPERATURE_SERVICE)
new MicroBitTemperatureService(*ble);
#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();
}
/**
* Change the output power level of the transmitter to the given value.
*
* @param power a value in the range 0..7, where 0 is the lowest power and 7 is the highest.
* @return MICROBIT_OK on success, or MICROBIT_INVALID_PARAMETER if the value is out of range.
*
*/
int MicroBitBLEManager::setTransmitPower(int power)
{
if (power < 0 || power >= MICROBIT_BLE_POWER_LEVELS)
return MICROBIT_INVALID_PARAMETER;
if (ble->gap().setTxPower(MICROBIT_BLE_POWER_LEVEL[power]) != NRF_SUCCESS)
return MICROBIT_NOT_SUPPORTED;
return MICROBIT_OK;
}
/**
* Determines the number of devices currently bonded with this micro:bit
* @return The number of active bonds.
*/
int MicroBitBLEManager::getBondCount()
{
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);
return whitelist.size;
}
/**
* A request to pair has been received from a BLE device.
* If we're in pairing mode, display the passkey to the user.
* Also, purge the binding table if it has reached capacity.
*/
void MicroBitBLEManager::pairingRequested(ManagedString passKey)
{
// Update our mode to display the passkey.
this->passKey = passKey;
this->pairingStatus = MICROBIT_BLE_PAIR_REQUEST;
}
/**
* A pairing request has been sucesfully completed.
* If we're in pairing mode, display feedback to the user.
*/
void MicroBitBLEManager::pairingComplete(bool success)
{
this->pairingStatus = MICROBIT_BLE_PAIR_COMPLETE;
if(success)
this->pairingStatus |= MICROBIT_BLE_PAIR_SUCCESSFUL;
}
/**
* 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();
}
}
/**
* Displays the device's ID code as a histogram on the LED matrix display.
*/
void MicroBitBLEManager::showNameHistogram(MicroBitDisplay &display)
{
uint32_t n = NRF_FICR->DEVICEID[1];
int ld = 1;
int d = MICROBIT_DFU_HISTOGRAM_HEIGHT;
int h;
display.clear();
for (int i=0; i<MICROBIT_DFU_HISTOGRAM_WIDTH;i++)
{
h = (n % d) / ld;
n -= h;
d *= MICROBIT_DFU_HISTOGRAM_HEIGHT;
ld *= MICROBIT_DFU_HISTOGRAM_HEIGHT;
for (int j=0; j<h+1; j++)
display.image.setPixelValue(MICROBIT_DFU_HISTOGRAM_WIDTH-i-1, MICROBIT_DFU_HISTOGRAM_HEIGHT-j-1, 255);
}
}
Reference in New Issue View Git Blame Copy Permalink