ACL packet recombination (694027e9) · Commits · e / os / android_packages_modules_Bluetooth

system/gd/hal/hci_hal_host_rootcanal.cc

+2 −2

Original line number	Diff line number	Diff line
		@@ -42,7 +42,7 @@ constexpr uint8_t kH4HeaderSize = 1;
		constexpr uint8_t kHciAclHeaderSize = 4;
		constexpr uint8_t kHciScoHeaderSize = 3;
		constexpr uint8_t kHciEvtHeaderSize = 2;
		constexpr int kBufSize = 1024;
		constexpr int kBufSize = 1024 + 4 + 1; // DeviceProperties::acl_data_packet_size_ + ACL header + H4 header

		int ConnectToRootCanal(const std::string& server, int port) {
		int socket_fd = socket(AF_INET, SOCK_STREAM, 0);
		@@ -238,7 +238,7 @@ class HciHalHostRootcanal : public HciHal {
		ASSERT_LOG(received_size != -1, "Can't receive from socket: %s", strerror(errno));
		ASSERT_LOG(received_size == kHciAclHeaderSize, "malformed ACL header received");

		uint16_t hci_acl_data_total_length = buf[4] * 256 + buf[3];
		uint16_t hci_acl_data_total_length = (buf[4] << 8) + buf[3];
		int payload_size;
		RUN_NO_INTR(payload_size = recv(sock_fd_, buf + kH4HeaderSize + kHciAclHeaderSize, hci_acl_data_total_length, 0));
		ASSERT_LOG(payload_size != -1, "Can't receive from socket: %s", strerror(errno));

system/gd/hci/acl_manager.cc

+97 −32

Original line number	Diff line number	Diff line
		@@ -36,10 +36,36 @@ constexpr size_t kMaxQueuedPacketsPerConnection = 10;
		using common::Bind;
		using common::BindOnce;

		namespace {
		class PacketViewForRecombination : public packet::PacketView<kLittleEndian> {
		public:
		PacketViewForRecombination(const PacketView& packetView) : PacketView(packetView) {}
		void AppendPacketView(packet::PacketView<kLittleEndian> to_append) {
		Append(to_append);
		}
		};

		constexpr int kL2capBasicFrameHeaderSize = 4;

		// Per spec 5.1 Vol 2 Part B 5.3, ACL link shall carry L2CAP data. Therefore, an ACL packet shall contain L2CAP PDU.
		// This function returns the PDU size of the L2CAP data if it's a starting packet. Returns 0 if it's invalid.
		uint16_t GetL2capPduSize(AclPacketView packet) {
		auto l2cap_payload = packet.GetPayload();
		if (l2cap_payload.size() < kL2capBasicFrameHeaderSize) {
		LOG_ERROR("Controller sent an invalid L2CAP starting packet!");
		return 0;
		}
		return (l2cap_payload.at(1) << 8) + l2cap_payload.at(0);
		}

		} // namespace

		struct AclManager::acl_connection {
		acl_connection(AddressWithType address_with_type) : address_with_type_(address_with_type) {}
		acl_connection(AddressWithType address_with_type, os::Handler* handler)
		: address_with_type_(address_with_type), handler_(handler) {}
		friend AclConnection;
		AddressWithType address_with_type_;
		os::Handler* handler_;
		std::unique_ptr<AclConnection::Queue> queue_ = std::make_unique<AclConnection::Queue>(10);
		bool is_disconnected_ = false;
		ErrorCode disconnect_reason_;
		@@ -54,9 +80,70 @@ struct AclManager::acl_connection {
		bool is_registered_ = false;
		// Credits: Track the number of packets which have been sent to the controller
		uint16_t number_of_sent_packets_ = 0;
		bool enqueue_registered_{false};
		PacketViewForRecombination recombination_stage_{std::make_shared<std::vector<uint8_t>>()};
		int remaining_sdu_continuation_packet_size_ = 0;
		bool enqueue_registered_ = false;
		std::queue<packet::PacketView<kLittleEndian>> incoming_queue_;

		std::unique_ptr<packet::PacketView<kLittleEndian>> on_incoming_data_ready() {
		auto packet = incoming_queue_.front();
		incoming_queue_.pop();
		if (incoming_queue_.empty()) {
		auto queue_end = queue_->GetDownEnd();
		queue_end->UnregisterEnqueue();
		enqueue_registered_ = false;
		}
		return std::make_unique<PacketView<kLittleEndian>>(packet);
		}

		void on_incoming_packet(AclPacketView packet) {
		// TODO: What happens if the connection is stalled and fills up?
		PacketView<kLittleEndian> payload = packet.GetPayload();
		auto payload_size = payload.size();
		auto packet_boundary_flag = packet.GetPacketBoundaryFlag();
		if (packet_boundary_flag == PacketBoundaryFlag::FIRST_NON_AUTOMATICALLY_FLUSHABLE) {
		LOG_ERROR("Controller is not allowed to send FIRST_NON_AUTOMATICALLY_FLUSHABLE to host except loopback mode");
		return;
		}
		if (packet_boundary_flag == PacketBoundaryFlag::CONTINUING_FRAGMENT) {
		if (remaining_sdu_continuation_packet_size_ < payload_size) {
		LOG_WARN("Remote sent unexpected L2CAP PDU. Drop the entire L2CAP PDU");
		recombination_stage_ = PacketViewForRecombination(std::make_shared<std::vector<uint8_t>>());
		remaining_sdu_continuation_packet_size_ = 0;
		return;
		}
		remaining_sdu_continuation_packet_size_ -= payload_size;
		recombination_stage_.AppendPacketView(payload);
		if (remaining_sdu_continuation_packet_size_ != 0) {
		return;
		} else {
		payload = recombination_stage_;
		}
		} else if (packet_boundary_flag == PacketBoundaryFlag::FIRST_AUTOMATICALLY_FLUSHABLE) {
		if (recombination_stage_.size() > 0) {
		LOG_ERROR("Controller sent a starting packet without finishing previous packet. Drop previous one.");
		}
		auto l2cap_pdu_size = GetL2capPduSize(packet);
		remaining_sdu_continuation_packet_size_ = l2cap_pdu_size - (payload_size - kL2capBasicFrameHeaderSize);
		if (remaining_sdu_continuation_packet_size_ > 0) {
		recombination_stage_ = payload;
		return;
		}
		}
		if (incoming_queue_.size() > kMaxQueuedPacketsPerConnection) {
		LOG_ERROR("Dropping packet due to congestion from remote:%s", address_with_type_.ToString().c_str());
		return;
		}

		incoming_queue_.push(payload);
		if (!enqueue_registered_) {
		enqueue_registered_ = true;
		auto queue_end = queue_->GetDownEnd();
		queue_end->RegisterEnqueue(
		handler_, common::Bind(&AclManager::acl_connection::on_incoming_data_ready, common::Unretained(this)));
		}
		}

		void call_disconnect_callback() {
		disconnect_handler_->Post(BindOnce(std::move(on_disconnect_callback_), disconnect_reason_));
		}
		@@ -225,17 +312,6 @@ struct AclManager::impl {
		return std::unique_ptr<AclPacketBuilder>(raw_pointer);
		}

		std::unique_ptr<packet::PacketView<kLittleEndian>> OnIncomingReadReady(AclManager::acl_connection* connection) {
		auto packet = connection->incoming_queue_.front();
		connection->incoming_queue_.pop();
		if (connection->incoming_queue_.empty()) {
		auto queue_end = connection->queue_->GetDownEnd();
		queue_end->UnregisterEnqueue();
		connection->enqueue_registered_ = false;
		}
		return std::make_unique<PacketView<kLittleEndian>>(packet);
		}

		void dequeue_and_route_acl_packet_to_connection() {
		auto packet = hci_queue_end_->TryDequeue();
		ASSERT(packet != nullptr);
		@@ -252,23 +328,8 @@ struct AclManager::impl {
		LOG_INFO("Dropping packet of size %zu to unknown connection 0x%0hx", packet->size(), handle);
		return;
		}
		// TODO: What happens if the connection is stalled and fills up?
		// TODO hsz: define enqueue callback
		auto queue_end = connection_pair->second.queue_->GetDownEnd();
		PacketView<kLittleEndian> payload = packet->GetPayload();

		if (connection_pair->second.incoming_queue_.size() > kMaxQueuedPacketsPerConnection) {
		LOG_INFO("Dropping packet due to congestion from remote:%s",
		connection_pair->second.address_with_type_.ToString().c_str());
		return;
		}

		connection_pair->second.incoming_queue_.push(payload);
		if (!connection_pair->second.enqueue_registered_) {
		connection_pair->second.enqueue_registered_ = true;
		queue_end->RegisterEnqueue(handler_, common::Bind(&AclManager::impl::OnIncomingReadReady,
		common::Unretained(this), &connection_pair->second));
		}
		connection_pair->second.on_incoming_packet(*packet);
		}

		void on_incoming_connection(EventPacketView packet) {
		@@ -328,7 +389,8 @@ struct AclManager::impl {
		// TODO: Check and save other connection parameters
		uint16_t handle = connection_complete.GetConnectionHandle();
		ASSERT(acl_connections_.count(handle) == 0);
		acl_connections_.emplace(handle, address_with_type);
		acl_connections_.emplace(std::piecewise_construct, std::forward_as_tuple(handle),
		std::forward_as_tuple(address_with_type, handler_));
		if (acl_connections_.size() == 1 && fragments_to_send_.size() == 0) {
		start_round_robin();
		}
		@@ -361,7 +423,8 @@ struct AclManager::impl {
		// TODO: Check and save other connection parameters
		uint16_t handle = connection_complete.GetConnectionHandle();
		ASSERT(acl_connections_.count(handle) == 0);
		acl_connections_.emplace(handle, reporting_address_with_type);
		acl_connections_.emplace(std::piecewise_construct, std::forward_as_tuple(handle),
		std::forward_as_tuple(reporting_address_with_type, handler_));
		if (acl_connections_.size() == 1 && fragments_to_send_.size() == 0) {
		start_round_robin();
		}
		@@ -386,7 +449,9 @@ struct AclManager::impl {
		}
		uint16_t handle = connection_complete.GetConnectionHandle();
		ASSERT(acl_connections_.count(handle) == 0);
		acl_connections_.emplace(handle, AddressWithType{address, AddressType::PUBLIC_DEVICE_ADDRESS});
		acl_connections_.emplace(
		std::piecewise_construct, std::forward_as_tuple(handle),
		std::forward_as_tuple(AddressWithType{address, AddressType::PUBLIC_DEVICE_ADDRESS}, handler_));
		if (acl_connections_.size() == 1 && fragments_to_send_.size() == 0) {
		start_round_robin();
		}

system/gd/hci/acl_manager_test.cc

+2 −0

Original line number	Diff line number	Diff line
		@@ -54,6 +54,8 @@ PacketView<kLittleEndian> GetPacketView(std::unique_ptr<packet::BasePacketBuilde
		std::unique_ptr<BasePacketBuilder> NextPayload(uint16_t handle) {
		static uint32_t packet_number = 1;
		auto payload = std::make_unique<RawBuilder>();
		payload->AddOctets2(6); // L2CAP PDU size
		payload->AddOctets2(2); // L2CAP CID
		payload->AddOctets2(handle);
		payload->AddOctets4(packet_number++);
		return std::move(payload);

system/gd/hci/cert/acl_manager_test.py

+110 −3

Original line number	Diff line number	Diff line
		@@ -159,9 +159,11 @@ class AclManagerTest(GdFacadeOnlyBaseTestClass):

		self.enqueue_acl_data(
		cert_handle, hci_packets.PacketBoundaryFlag.
		FIRST_NON_AUTOMATICALLY_FLUSHABLE,
		FIRST_AUTOMATICALLY_FLUSHABLE,
		hci_packets.BroadcastFlag.POINT_TO_POINT,
		bytes(b'This is just SomeAclData from the Cert'))
		bytes(
		b'\x26\x00\x07\x00This is just SomeAclData from the Cert'
		))

		# DUT gets a connection complete event and sends and receives
		connection_event_asserts = EventAsserts(connection_event_stream)
		@@ -172,7 +174,8 @@ class AclManagerTest(GdFacadeOnlyBaseTestClass):
		acl_manager_facade.AclData(
		handle=handle,
		payload=bytes(
		b'This is just SomeMoreAclData from the DUT')))
		b'\x29\x00\x07\x00This is just SomeMoreAclData from the DUT'
		)))

		acl_data_asserts = EventAsserts(acl_data_stream)
		cert_acl_data_asserts = EventAsserts(cert_acl_data_stream)
		@@ -180,3 +183,107 @@ class AclManagerTest(GdFacadeOnlyBaseTestClass):
		lambda packet: b'SomeMoreAclData' in packet.data)
		acl_data_asserts.assert_event_occurs(
		lambda packet: b'SomeAclData' in packet.payload)

		def test_recombination_l2cap_packet(self):
		self.register_for_event(hci_packets.EventCode.CONNECTION_REQUEST)
		self.register_for_event(hci_packets.EventCode.CONNECTION_COMPLETE)
		with EventCallbackStream(self.cert_device.hci.FetchEvents(empty_proto.Empty())) as cert_hci_event_stream, \
		EventCallbackStream(self.cert_device.hci.FetchAclPackets(empty_proto.Empty())) as cert_acl_data_stream, \
		EventCallbackStream(self.device_under_test.hci_acl_manager.FetchAclData(empty_proto.Empty())) as acl_data_stream:

		# CERT Enables scans and gets its address
		self.enqueue_hci_command(
		hci_packets.WriteScanEnableBuilder(
		hci_packets.ScanEnable.INQUIRY_AND_PAGE_SCAN), True)

		cert_address = None

		def get_address_from_complete(packet):
		packet_bytes = packet.event
		if b'\x0e\x0a\x01\x09\x10' in packet_bytes:
		nonlocal cert_address
		addr_view = hci_packets.ReadBdAddrCompleteView(
		hci_packets.CommandCompleteView(
		hci_packets.EventPacketView(
		bt_packets.PacketViewLittleEndian(
		list(packet_bytes)))))
		cert_address = addr_view.GetBdAddr()
		return True
		return False

		self.enqueue_hci_command(hci_packets.ReadBdAddrBuilder(), True)

		cert_hci_event_asserts = EventAsserts(cert_hci_event_stream)
		cert_hci_event_asserts.assert_event_occurs(
		get_address_from_complete)

		with EventCallbackStream(
		self.device_under_test.hci_acl_manager.CreateConnection(
		acl_manager_facade.ConnectionMsg(
		address_type=int(
		hci_packets.AddressType.PUBLIC_DEVICE_ADDRESS),
		address=bytes(cert_address,
		'utf8')))) as connection_event_stream:
		connection_request = None

		def get_connect_request(packet):
		if b'\x04\x0a' in packet.event:
		nonlocal connection_request
		connection_request = hci_packets.ConnectionRequestView(
		hci_packets.EventPacketView(
		bt_packets.PacketViewLittleEndian(
		list(packet.event))))
		return True
		return False

		# Cert Accepts
		cert_hci_event_asserts.assert_event_occurs(get_connect_request)
		self.enqueue_hci_command(
		hci_packets.AcceptConnectionRequestBuilder(
		connection_request.GetBdAddr(),
		hci_packets.AcceptConnectionRequestRole.REMAIN_SLAVE),
		False)

		# Cert gets ConnectionComplete with a handle and sends ACL data
		handle = 0xfff

		def get_handle(packet):
		packet_bytes = packet.event
		if b'\x03\x0b\x00' in packet_bytes:
		nonlocal handle
		cc_view = hci_packets.ConnectionCompleteView(
		hci_packets.EventPacketView(
		bt_packets.PacketViewLittleEndian(
		list(packet_bytes))))
		handle = cc_view.GetConnectionHandle()
		return True
		return False

		cert_hci_event_asserts.assert_event_occurs(get_handle)
		cert_handle = handle

		acl_data_asserts = EventAsserts(acl_data_stream)

		self.enqueue_acl_data(
		cert_handle, hci_packets.PacketBoundaryFlag.
		FIRST_AUTOMATICALLY_FLUSHABLE,
		hci_packets.BroadcastFlag.POINT_TO_POINT,
		bytes(b'\x06\x00\x07\x00Hello'))
		self.enqueue_acl_data(
		cert_handle,
		hci_packets.PacketBoundaryFlag.CONTINUING_FRAGMENT,
		hci_packets.BroadcastFlag.POINT_TO_POINT, bytes(b'!'))
		self.enqueue_acl_data(
		cert_handle, hci_packets.PacketBoundaryFlag.
		FIRST_AUTOMATICALLY_FLUSHABLE,
		hci_packets.BroadcastFlag.POINT_TO_POINT,
		bytes(b'\x88\x13\x07\x00' + b'Hello' * 1000))

		# DUT gets a connection complete event and sends and receives
		connection_event_asserts = EventAsserts(connection_event_stream)
		connection_event_asserts.assert_event_occurs(get_handle)

		acl_data_asserts.assert_event_occurs(
		lambda packet: b'Hello!' in packet.payload)
		acl_data_asserts.assert_event_occurs(
		lambda packet: b'Hello' * 1000 in packet.payload)

system/vendor_libs/test_vendor_lib/model/controller/link_layer_controller.cc

+21 −10

Original line number	Diff line number	Diff line
		@@ -139,11 +139,9 @@ ErrorCode LinkLayerController::SendAclToRemote(
		std::make_unique<bluetooth::packet::RawBuilder>();
		std::vector<uint8_t> payload_bytes(acl_payload.begin(), acl_payload.end());

		constexpr auto pb_flag_controller_to_host =
		bluetooth::hci::PacketBoundaryFlag::FIRST_AUTOMATICALLY_FLUSHABLE;
		uint16_t first_two_bytes =
		static_cast<uint16_t>(acl_packet.GetHandle()) +
		(static_cast<uint16_t>(pb_flag_controller_to_host) << 12) +
		(static_cast<uint16_t>(acl_packet.GetPacketBoundaryFlag()) << 12) +
		(static_cast<uint16_t>(acl_packet.GetBroadcastFlag()) << 14);
		raw_builder_ptr->AddOctets2(first_two_bytes);
		raw_builder_ptr->AddOctets2(static_cast<uint16_t>(payload_bytes.size()));
		@@ -303,15 +301,28 @@ void LinkLayerController::IncomingAclPacket(

		std::vector<uint8_t> payload_data(acl_view.GetPayload().begin(),
		acl_view.GetPayload().end());
		uint16_t acl_buffer_size = properties_.GetAclDataPacketSize();
		int num_packets =
		(payload_data.size() + acl_buffer_size - 1) / acl_buffer_size;

		auto pb_flag_controller_to_host = acl_view.GetPacketBoundaryFlag();
		for (int i = 0; i < num_packets; i++) {
		size_t start_index = acl_buffer_size * i;
		size_t end_index =
		std::min(start_index + acl_buffer_size, payload_data.size());
		std::vector<uint8_t> fragment(&payload_data[start_index],
		&payload_data[end_index]);
		std::unique_ptr<bluetooth::packet::RawBuilder> raw_builder_ptr =
		std::make_unique<bluetooth::packet::RawBuilder>(payload_data);

		std::make_unique<bluetooth::packet::RawBuilder>(fragment);
		auto acl_packet = bluetooth::hci::AclPacketBuilder::Create(
		local_handle, acl_view.GetPacketBoundaryFlag(),
		acl_view.GetBroadcastFlag(), std::move(raw_builder_ptr));
		local_handle, pb_flag_controller_to_host, acl_view.GetBroadcastFlag(),
		std::move(raw_builder_ptr));
		pb_flag_controller_to_host =
		bluetooth::hci::PacketBoundaryFlag::CONTINUING_FRAGMENT;

		send_acl_(std::move(acl_packet));
		}
		}

		void LinkLayerController::IncomingRemoteNameRequest(
		model::packets::LinkLayerPacketView packet) {