Add Extended Advertising support in Nearby Connections layer

PiperOrigin-RevId: 452112156
2026-09-16 15:36:12 -04:00 · 2022-05-31 12:29:18 -07:00
parent 93bc497872
commit b4b74ca5b4
2 changed files with 162 additions and 11 deletions
@@ -77,6 +77,11 @@ bool BleMedium::StartAdvertising(

  DataWriter data_writer;

+  // TODO(b/234229562): Add parsing logic for fast_advertisement_service_uuid
+  // and insert into the 0x16 Service Data field in the BLE advertisement when
+  // Fast Advertisement is enabled. For Extended Advertising, use the same
+  // hardcoded Copresence service uuid 0xFEF3.
+
  // Copresence Service UUID 0xfef3 (little-endian)
  data_writer.WriteUInt16(kCopresenceServiceUuid);

@@ -93,19 +98,48 @@ bool BleMedium::StartAdvertising(
  data_sections.Append(service_data);
  advertisement_.DataSections() = data_sections;

-  publisher_ = BluetoothLEAdvertisementPublisher(advertisement_);
+  // Use Extended Advertising if Fast Advertisement Service Uuid is empty string
+  // because the long format advertisement will be used
+  if (fast_advertisement_service_uuid.empty()) {
+    publisher_ = BluetoothLEAdvertisementPublisher(advertisement_);
+    publisher_.UseExtendedAdvertisement(true);

-  publisher_token_ =
-      publisher_.StatusChanged({this, &BleMedium::PublisherHandler});
+    publisher_token_ =
+        publisher_.StatusChanged({this, &BleMedium::PublisherHandler});

-  publisher_started_promise_ = std::promise<PublisherState>();
+    publisher_started_promise_ = std::promise<PublisherState>();

-  std::future<PublisherState> publisher_state_future =
-      publisher_started_promise_.get_future();
+    std::future<PublisherState> publisher_state_future =
+        publisher_started_promise_.get_future();

-  publisher_.Start();
+    publisher_.Start();

-  return publisher_state_future.get() == PublisherState::kStarted;
+    return publisher_state_future.get() == PublisherState::kStarted;
+  } else {
+    // Extended Advertisement not supported, must make sure advertisement_bytes
+    // is less than 27 bytes
+    if (advertisement_bytes.size() <= 27) {
+      publisher_ = BluetoothLEAdvertisementPublisher(advertisement_);
+      publisher_.UseExtendedAdvertisement(false);
+
+      publisher_token_ =
+          publisher_.StatusChanged({this, &BleMedium::PublisherHandler});
+
+      publisher_started_promise_ = std::promise<PublisherState>();
+
+      std::future<PublisherState> publisher_state_future =
+          publisher_started_promise_.get_future();
+
+      publisher_.Start();
+
+      return publisher_state_future.get() == PublisherState::kStarted;
+    } else {
+      // otherwise no-op
+      NEARBY_LOGS(INFO) << "Everyone Mode unavailable for hardware that does "
+                           "not support Extended Advertising.";
+      return false;
+    }
+  }
 }

 bool BleMedium::StopAdvertising(const std::string& service_id) {
@@ -123,6 +157,7 @@ bool BleMedium::StopAdvertising(const std::string& service_id) {
  return publisher_state_future.get() == PublisherState::kStopped;
 }

+// TODO(b/234229557): Add BlePeripheral discovery logic
 bool BleMedium::StartScanning(
    const std::string& service_id,
    const std::string& fast_advertisement_service_uuid,
@@ -158,7 +193,6 @@ bool BleMedium::StartScanning(

 bool BleMedium::StopScanning(const std::string& service_id) {
  absl::MutexLock lock(&mutex_);
-
  NEARBY_LOGS(INFO) << "Windows Ble StopScanning: service_id=" << service_id;

  watcher_stopped_promise_ = std::promise<WatcherState>();
@@ -36,7 +36,7 @@ constexpr uint8_t kFastAdvertisementFlagBitmask = 0x02;
 constexpr uint8_t kPcpBitmask = 0x1F;
 constexpr uint8_t kVisibilityBitmask = 0x01;

-TEST(BleMedium, DISABLED_StartAdvertising) {
+TEST(BleMedium, DISABLED_StartAdvertising_FastAdvertisement) {
  BluetoothAdapter bluetoothAdapter;
  BleMedium ble_medium(bluetoothAdapter);

@@ -61,7 +61,7 @@ TEST(BleMedium, DISABLED_StartAdvertising) {

  // (1 byte) body_length
  advertising_data_byte_array.at(1) = static_cast<unsigned char>(
-      0x19);  // always 25 bytes for Fast Advertisement
+      0x17);  // always 23 bytes for Fast Advertisement

  // (1 byte) Nearby Connection version [3-bits] + pcp [5-bits]
  uint8_t ble_connections_version =
@@ -117,6 +117,123 @@ TEST(BleMedium, DISABLED_StartAdvertising) {
      ble_medium.StartAdvertising("NearbyShare", advertising_data, "\xfe\xf3"));
 }

+TEST(BleMedium, DISABLED_StartAdvertising_ExtendedAdvertising) {
+  BluetoothAdapter bluetoothAdapter;
+  BleMedium ble_medium(bluetoothAdapter);
+
+  std::array<char, 167> advertising_data_byte_array;
+
+  // (1 byte) version [3-bits] + socket_version [3-bits] +
+  // fast_advertisement_flag [1-bit] + reserved [1-bit]
+  uint8_t ble_medium_version = 0x02;  // mediums::BleAdvertisement::Version::kV2
+  uint8_t socket_version =
+      0x02;  // mediums::BleAdvertisement::SocketVersion::kV2
+  bool fast_advertisement = false;  // Is Fast Advertisement
+
+  uint8_t ble_medium_advertisement_metadata_byte =
+      (ble_medium_version << 5) & kVersionBitmask;
+  ble_medium_advertisement_metadata_byte |=
+      (socket_version << 2) & kSocketVersionBitmask;
+  ble_medium_advertisement_metadata_byte |=
+      ((fast_advertisement ? 1 : 0) << 1) & kFastAdvertisementFlagBitmask;
+
+  advertising_data_byte_array.at(0) =
+      static_cast<unsigned char>(ble_medium_advertisement_metadata_byte);
+
+  // (3 bytes) service_id_hash
+  for (int i = 0; i < 3; ++i) {
+    advertising_data_byte_array.at(1 + i) = static_cast<unsigned char>(0x00);
+  }
+
+  // (4 bytes) body_length
+  advertising_data_byte_array.at(7) = static_cast<unsigned char>(
+      0x9C);  // max 156 bytes for Extended Advertising
+
+  // (1 byte) Nearby Connection version [3-bits] + pcp [5-bits]
+  uint8_t ble_connections_version =
+      0x01;            // connections::BleAdvertisement::Version::kV1
+  uint8_t pcp = 0x02;  // connections::Pcp::kP2pCluster
+
+  uint8_t ble_connections_advertisement_metadata_byte =
+      (ble_connections_version << 5) & kVersionBitmask;
+  ble_connections_advertisement_metadata_byte |= pcp & kPcpBitmask;
+  advertising_data_byte_array.at(8) =
+      static_cast<unsigned char>(ble_connections_advertisement_metadata_byte);
+
+  // (3 bytes) service_id_hash
+  for (int i = 0; i < 3; ++i) {
+    advertising_data_byte_array.at(9 + i) = static_cast<unsigned char>(0x00);
+  }
+
+  // (4 bytes) endpoint_id
+  for (int i = 0; i < 4; ++i) {
+    advertising_data_byte_array.at(12 + i) = static_cast<unsigned char>(0x00);
+  }
+
+  // (1 byte) endpoint_info_size
+  advertising_data_byte_array.at(16) = static_cast<unsigned char>(
+      0x83);  // max 131-bytes for Extended Advertising
+
+  // =========endpoint_info [Max 131-bytes]============
+  // (1 byte) Nearby Share version [3-bits] + visibility [1-bit] + reserved
+  // [4-bits]
+  uint8_t nearby_share_version = 0x00;  // nearby share v1
+  uint8_t visibility = 0x00;  // [placeholder] sharing::Visibility::kAllContacts
+
+  uint8_t nearby_share_metadata_byte =
+      (nearby_share_version << 5) & kVersionBitmask;
+  nearby_share_metadata_byte |= ((visibility & kVisibilityBitmask) << 4);
+
+  advertising_data_byte_array.at(17) = static_cast<unsigned char>(0x00);
+
+  // (2 bytes) salt
+  for (int i = 0; i < 2; ++i) {
+    advertising_data_byte_array.at(18 + i) = static_cast<unsigned char>(0x00);
+  }
+
+  // (14 bytes) encrypted_metadata_key
+  for (int i = 0; i < 14; ++i) {
+    advertising_data_byte_array.at(20 + i) = static_cast<unsigned char>(0x00);
+  }
+
+  // [optional]
+  // (1 byte) human_readable_name_size
+  advertising_data_byte_array.at(34) = static_cast<unsigned char>(0x72);
+
+  // [optional]
+  // (max 114 bytes) human_readable_name
+  for (int i = 0; i < 114; ++i) {
+    advertising_data_byte_array.at(35 + i) = static_cast<unsigned char>(0x00);
+  }
+  // =========endpoint_info [131-bytes]============
+
+  // (6 bytes) bluetooth_mac_address
+  for (int i = 0; i < 6; ++i) {
+    advertising_data_byte_array.at(149 + i) = static_cast<unsigned char>(0x00);
+  }
+
+  // (1 byte) uwb_address_size
+  advertising_data_byte_array.at(155) = static_cast<unsigned char>(0x72);
+
+  // (8 bytes) uwb_address
+  for (int i = 0; i < 6; ++i) {
+    advertising_data_byte_array.at(156 + i) = static_cast<unsigned char>(0x00);
+  }
+
+  // (1 byte) extra_field [web_rtc_connectable]
+  advertising_data_byte_array.at(164) = static_cast<unsigned char>(0x72);
+
+  // (2 bytes) device_token
+  for (int i = 0; i < 2; ++i) {
+    advertising_data_byte_array.at(165 + i) = static_cast<unsigned char>(0x00);
+  }
+
+  ByteArray advertising_data(advertising_data_byte_array);
+
+  EXPECT_TRUE(
+      ble_medium.StartAdvertising("NearbyShare", advertising_data, ""));
+}
+
 TEST(BleMedium, DISABLED_StopAdvertising) {
  BluetoothAdapter bluetoothAdapter;
  BleMedium ble_medium(bluetoothAdapter);