Allow selecting BT adapter via BD address

.gitignore

@@ -6,6 +6,7 @@ cscope.*
 cmd/tesla-control/tesla-control
 cmd/tesla-auth-token/tesla-auth-token
 cmd/tesla-key-setup/tesla-key-setup
+cmd/test-ble/test-ble
 examples/unlock/unlock
 examples/ble/ble
 *.DS_Store

cmd/test-ble/main.go

@@ -0,0 +1,39 @@
+package main
+
+import (
+	"flag"
+	"strings"
+
+	goble "github.com/go-ble/ble"
+	"github.com/teslamotors/vehicle-command/internal/log"
+	"github.com/teslamotors/vehicle-command/pkg/connector/ble"
+)
+
+var (
+	bdAddr = flag.String("bdAddr", "", "Bluetooth device address")
+)
+
+func main() {
+	flag.Parse()
+	log.SetLevel(log.LevelDebug)
+
+	var err error
+	if bdAddr != nil {
+		log.Info("Target BLE device address: %s", *bdAddr)
+		err = ble.InitDevice(goble.NewAddr(*bdAddr))
+	} else {
+		log.Info("Using first available BLE device")
+		err = ble.InitDevice(nil)
+	}
+
+	if err != nil {
+		if strings.Contains(err.Error(), "failed to find a BLE device") {
+			log.Error("No BLE device found")
+		} else {
+			log.Error("Failed to initialize BLE device: %v", err)
+		}
+		return
+	}
+
+	log.Info("BLE is working")
+}

pkg/cli/config.go

@@ -66,6 +66,7 @@ import (
 	"github.com/teslamotors/vehicle-command/pkg/vehicle"
 
 	"github.com/99designs/keyring"
+	goble "github.com/go-ble/ble"
 )
 
 var DomainsByName = map[string]protocol.Domain{
@@ -150,6 +151,7 @@ type Config struct {
 	DisableCache     bool
 	Backend          keyring.Config
 	BackendType      backendType
+	BdAddress        string
 	Debug            bool // Enable keyring debug messages
 
 	// Domains can limit a vehicle connection to relevant subsystems, which can reduce
@@ -183,6 +185,9 @@ func (c *Config) RegisterCommandLineFlags() {
 	if c.Flags.isSet(FlagVIN) {
 		flag.StringVar(&c.VIN, "vin", "", "Vehicle Identification Number. Defaults to $TESLA_VIN.")
 	}
+	if c.Flags.isSet(FlagBLE) {
+		flag.StringVar(&c.BdAddress, "bdAddr", "", "Bluetooth device address")
+	}
 	if c.Flags.isSet(FlagPrivateKey) {
 		if !c.Flags.isSet(FlagVIN) {
 			log.Debug("FlagPrivateKey is set but FlagVIN is not. A VIN is required to send vehicle commands.")
@@ -469,6 +474,14 @@ func (c *Config) ConnectRemote(ctx context.Context, skey protocol.ECDHPrivateKey
 
 // ConnectLocal connects to a vehicle over BLE.
 func (c *Config) ConnectLocal(ctx context.Context, skey protocol.ECDHPrivateKey) (car *vehicle.Vehicle, err error) {
+	var addr goble.Addr
+	if c.BdAddress != "" {
+		addr = goble.NewAddr(c.BdAddress)
+	}
+	err = ble.InitDevice(addr)
+	if err != nil {
+		return nil, err
+	}
 	conn, err := ble.NewConnection(ctx, c.VIN)
 	if err != nil {
 		return nil, err

pkg/connector/ble/ble.go

@@ -132,7 +132,23 @@ func VehicleLocalName(vin string) string {
 	return fmt.Sprintf("S%02xC", digest[:8])
 }
 
-func initDevice() error {
+// InitDevice initializes a device with the local Bluetooth device address.
+// If bdAddr is nil, the first available BLE device will be used.
+// On linux it is a MAC address, on MacOS it is a UUID.
+// If this function is not called before making a connection, the first available
+// BLE device will be used, and this function will return an error.
+// NOTE: Currently targeting an address is only supported on Linux.
+func InitDevice(bdAddr ble.Addr) error {
+	mu.Lock()
+	defer mu.Unlock()
+	if device != nil {
+		return fmt.Errorf("ble: device already initialized")
+	}
+
+	return initDevice(bdAddr)
+}
+
+func initDevice(bdAddr ble.Addr) error {
 	var err error
 	// We don't want concurrent calls to NewConnection that would defeat
 	// the point of reusing the existing BLE device. Note that this is not
@@ -141,7 +157,7 @@ func initDevice() error {
 		log.Debug("Reusing existing BLE device")
 	} else {
 		log.Debug("Creating new BLE device")
-		device, err = newDevice()
+		device, err = newDevice(bdAddr)
 		if err != nil {
 			return fmt.Errorf("failed to find a BLE device: %s", err)
 		}
@@ -150,13 +166,27 @@ func initDevice() error {
 	return nil
 }
 
+func StopDevice() error {
+	mu.Lock()
+	defer mu.Unlock()
+	if device == nil {
+		log.Debug("Closing a non-existent BLE device")
+		return nil
+	}
+	if err := device.Stop(); err != nil {
+		return fmt.Errorf("ble: failed to stop device: %s", err)
+	}
+	device = nil
+	return nil
+}
+
 type Advertisement = ble.Advertisement
 
 func ScanVehicleBeacon(ctx context.Context, vin string) (Advertisement, error) {
 	mu.Lock()
 	defer mu.Unlock()
 
-	if err := initDevice(); err != nil {
+	if err := initDevice(nil); err != nil {
 		return nil, err
 	}
 
@@ -235,7 +265,7 @@ func tryToConnect(ctx context.Context, vin string, target Advertisement) (*Conne
 	mu.Lock()
 	defer mu.Unlock()
 
-	if err = initDevice(); err != nil {
+	if err = initDevice(nil); err != nil {
 		return nil, false, err
 	}
 

pkg/connector/ble/device_darwin.go

@@ -3,9 +3,13 @@ package ble
 import (
 	"github.com/go-ble/ble"
 	"github.com/go-ble/ble/darwin"
+	"github.com/teslamotors/vehicle-command/internal/log"
 )
 
-func newDevice() (ble.Device, error) {
+func newDevice(bdAddr ble.Addr) (ble.Device, error) {
+	if bdAddr != nil || bdAddr.String() != "" {
+		log.Warning("Setting the Bluetooth device address is not supported on Darwin")
+	}
 	device, err := darwin.NewDevice()
 	if err != nil {
 		return nil, err

pkg/connector/ble/device_linux.go

@@ -1,10 +1,15 @@
 package ble
 
 import (
+	"fmt"
+	"strings"
+	"time"
+
 	"github.com/go-ble/ble"
 	"github.com/go-ble/ble/linux"
+	"github.com/go-ble/ble/linux/hci"
 	"github.com/go-ble/ble/linux/hci/cmd"
-	"time"
+	"github.com/teslamotors/vehicle-command/internal/log"
 )
 
 const bleTimeout = 20 * time.Second
@@ -19,8 +24,55 @@ var scanParams = cmd.LESetScanParameters{
 	ScanningFilterPolicy: 2,    // Basic filtered
 }
 
-func newDevice() (ble.Device, error) {
-	device, err := linux.NewDevice(ble.OptListenerTimeout(bleTimeout), ble.OptDialerTimeout(bleTimeout), ble.OptScanParams(scanParams))
+func newDevice(bdAddr ble.Addr) (ble.Device, error) {
+	maxHciDevices := 16
+	hciX := -1
+	log.Debug("Scanning for HCI devices")
+	bdAddrStr := ""
+	if bdAddr != nil {
+		bdAddrStr = bdAddr.String()
+	}
+	var lastErr error
+	for i := 0; i < maxHciDevices; i++ {
+		devHci, err := hci.NewHCI(ble.OptDeviceID(i))
+		if err != nil {
+			return nil, fmt.Errorf("can't create HCI %d: %v", i, err)
+		}
+
+		if err = devHci.Init(); err != nil {
+			if !strings.Contains(err.Error(), "no such device") {
+				lastErr = err
+				log.Debug("Can't init HCI %d: %v", i, err)
+			}
+			continue
+		}
+		if err = devHci.Close(); err != nil {
+			return nil, fmt.Errorf("can't close HCI %d: %v", i, err)
+		}
+
+		log.Debug("Found HCI %d: %s", i, devHci.Addr())
+		if bdAddrStr == "" || devHci.Addr().String() == bdAddrStr {
+			hciX = i
+			break
+		}
+	}
+
+	if hciX == -1 && lastErr != nil {
+		return nil, lastErr
+	} else if hciX == -1 {
+		return nil, fmt.Errorf("no device with address %s", bdAddr)
+	}
+	log.Debug("Using HCI %d", hciX)
+
+	opts := []ble.Option{
+		ble.OptDeviceID(hciX),
+		ble.OptListenerTimeout(bleTimeout),
+		ble.OptDialerTimeout(bleTimeout),
+		ble.OptScanParams(scanParams),
+	}
+
+	device, err := linux.NewDeviceWithName("vehicle-command", opts...)
+
 	if err != nil {
 		return nil, err
 	}

pkg/connector/ble/device_windows.go

@@ -2,9 +2,10 @@ package ble
 
 import (
 	"errors"
+
 	"github.com/go-ble/ble"
 )
 
-func newDevice() (ble.Device, error) {
+func newDevice(ble.Addr) (ble.Device, error) {
 	return nil, errors.New("not supported on Windows")
 }