AudioService: anonymize Bluetooth MAC addresses

Make sure APIs returning AudioDeviceAttributes from AudioService
anonymize the Bluetooth MAC addresses because those are considered
privacy sensitive.
Only expose the full MAC address to system and apps with BLUETOOTH_CONNECT
permission.

setters, getters and listeners for preferred device for strategy,
preferred device for capture preset and mute await connection are
modified:
- when entering AudioService, full MAC addresses are retrieved based on the
  known Bluetooth devices stored in AudioDeviceInventory.mDeviceInventory
- when exiting AudioService, MAC addresses are anonymized if the client
  app does not have BLUETOOTH_CONNECT permission or is not a system component

APIs based on AudioDeviceInfo do not need to be modified as the
AudioDeviceInfo MAC address is for the AudioPort cached in the app
process and AudioPorts are anonymized by the native audioserver before
being returned to client apps.

Bug: 285588444

Test: atest AudioManagerTest
Test: atest RoutingTest
Test: atest AudioCommunicationDeviceTest
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:4c1d23ed19823b2706866201eded0c556f83e018)
Merged-In: I67bbba2ba941c97138a068d640079b17650e3d86
Change-Id: I67bbba2ba941c97138a068d640079b17650e3d86

Author: Eric Laurent

media/java/android/media/AudioDeviceAttributes.java

@@ -68,7 +68,7 @@ public final class AudioDeviceAttributes implements Parcelable {
     /**
      * The unique address of the device. Some devices don't have addresses, only an empty string.
      */
-    private final @NonNull String mAddress;
+    private @NonNull String mAddress;
     /**
      * The non-unique name of the device. Some devices don't have names, only an empty string.
      * Should not be used as a unique identifier for a device.
@@ -186,6 +186,21 @@ public AudioDeviceAttributes(int nativeType, @NonNull String address, @NonNull S
         mAudioDescriptors = new ArrayList<>();
     }
 
+    /**
+     * @hide
+     * Copy Constructor.
+     * @param ada the copied AudioDeviceAttributes
+     */
+    public AudioDeviceAttributes(AudioDeviceAttributes ada) {
+        mRole = ada.getRole();
+        mType = ada.getType();
+        mAddress = ada.getAddress();
+        mName = ada.getName();
+        mNativeType = ada.getInternalType();
+        mAudioProfiles = ada.getAudioProfiles();
+        mAudioDescriptors = ada.getAudioDescriptors();
+    }
+
     /**
      * @hide
      * Returns the role of a device
@@ -216,6 +231,15 @@ public AudioDeviceAttributes(int nativeType, @NonNull String address, @NonNull S
         return mAddress;
     }
 
+    /**
+     * @hide
+     * Sets the device address. Only used by audio service.
+     */
+    public void setAddress(@NonNull String address) {
+        Objects.requireNonNull(address);
+        mAddress = address;
+    }
+
     /**
      * @hide
      * Returns the name of the audio device, or an empty string for devices without one

services/core/java/com/android/server/audio/AdiDeviceState.java

@@ -25,6 +25,7 @@
 import android.media.AudioDeviceInfo;
 import android.text.TextUtils;
 import android.util.Log;
+import android.util.Pair;
 
 import java.util.Objects;
 
@@ -43,6 +44,8 @@
     private final int mInternalDeviceType;
     @NonNull
     private final String mDeviceAddress;
+    /** Unique device id from internal device type and address. */
+    private final Pair<Integer, String> mDeviceId;
     private boolean mSAEnabled;
     private boolean mHasHeadTracker = false;
     private boolean mHeadTrackerEnabled;
@@ -68,6 +71,11 @@
         }
         mDeviceAddress = isBluetoothDevice(mInternalDeviceType) ? Objects.requireNonNull(
                 address) : "";
+        mDeviceId = new Pair<>(mInternalDeviceType, mDeviceAddress);
+    }
+
+    public Pair<Integer, String> getDeviceId() {
+        return mDeviceId;
     }
 
 
@@ -140,7 +148,8 @@ public int hashCode() {
 
     @Override
     public String toString() {
-        return "type: " + mDeviceType + "internal type: " + mInternalDeviceType
+        return "type: " + mDeviceType
+                + " internal type: 0x" + Integer.toHexString(mInternalDeviceType)
                 + " addr: " + mDeviceAddress + " enabled: " + mSAEnabled
                 + " HT: " + mHasHeadTracker + " HTenabled: " + mHeadTrackerEnabled;
     }

services/core/java/com/android/server/audio/AudioDeviceBroker.java

@@ -833,8 +833,8 @@ private void btMediaMetricRecord(@NonNull BluetoothDevice device, String state,
     }
 
     /*package*/ void registerStrategyPreferredDevicesDispatcher(
-            @NonNull IStrategyPreferredDevicesDispatcher dispatcher) {
-        mDeviceInventory.registerStrategyPreferredDevicesDispatcher(dispatcher);
+            @NonNull IStrategyPreferredDevicesDispatcher dispatcher, boolean isPrivileged) {
+        mDeviceInventory.registerStrategyPreferredDevicesDispatcher(dispatcher, isPrivileged);
     }
 
     /*package*/ void unregisterStrategyPreferredDevicesDispatcher(
@@ -852,15 +852,20 @@ private void btMediaMetricRecord(@NonNull BluetoothDevice device, String state,
     }
 
     /*package*/ void registerCapturePresetDevicesRoleDispatcher(
-            @NonNull ICapturePresetDevicesRoleDispatcher dispatcher) {
-        mDeviceInventory.registerCapturePresetDevicesRoleDispatcher(dispatcher);
+            @NonNull ICapturePresetDevicesRoleDispatcher dispatcher, boolean isPrivileged) {
+        mDeviceInventory.registerCapturePresetDevicesRoleDispatcher(dispatcher, isPrivileged);
     }
 
     /*package*/ void unregisterCapturePresetDevicesRoleDispatcher(
             @NonNull ICapturePresetDevicesRoleDispatcher dispatcher) {
         mDeviceInventory.unregisterCapturePresetDevicesRoleDispatcher(dispatcher);
     }
 
+    /* package */ List<AudioDeviceAttributes> anonymizeAudioDeviceAttributesListUnchecked(
+            List<AudioDeviceAttributes> devices) {
+        return mAudioService.anonymizeAudioDeviceAttributesListUnchecked(devices);
+    }
+
     /*package*/ void registerCommunicationDeviceDispatcher(
             @NonNull ICommunicationDeviceDispatcher dispatcher) {
         mCommDevDispatchers.register(dispatcher);

services/core/java/com/android/server/audio/AudioDeviceInventory.java

@@ -40,14 +40,17 @@
 import android.util.ArrayMap;
 import android.util.ArraySet;
 import android.util.Log;
+import android.util.Pair;
 import android.util.Slog;
 
 import com.android.internal.annotations.GuardedBy;
 import com.android.internal.annotations.VisibleForTesting;
 
 import java.io.PrintWriter;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.HashSet;
+import java.util.Iterator;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Objects;
@@ -74,31 +77,58 @@ public class AudioDeviceInventory {
 
     private final Object mDeviceInventoryLock = new Object();
     @GuardedBy("mDeviceInventoryLock")
-    private final ArrayList<AdiDeviceState> mDeviceInventory = new ArrayList<>(0);
-
+    private final HashMap<Pair<Integer, String>, AdiDeviceState> mDeviceInventory = new HashMap<>();
 
     List<AdiDeviceState> getImmutableDeviceInventory() {
         synchronized (mDeviceInventoryLock) {
-            return List.copyOf(mDeviceInventory);
+            return new ArrayList<AdiDeviceState>(mDeviceInventory.values());
         }
     }
 
     void addDeviceStateToInventory(AdiDeviceState deviceState) {
         synchronized (mDeviceInventoryLock) {
-            mDeviceInventory.add(deviceState);
+            mDeviceInventory.put(deviceState.getDeviceId(), deviceState);
+        }
+    }
+
+    /**
+     * Adds a new entry in mDeviceInventory if the AudioDeviceAttributes passed is an sink
+     * Bluetooth device and no corresponding entry already exists.
+     * @param ada the device to add if needed
+     */
+    void addAudioDeviceInInventoryIfNeeded(AudioDeviceAttributes ada) {
+        if (!AudioSystem.isBluetoothOutDevice(ada.getInternalType())) {
+            return;
+        }
+        synchronized (mDeviceInventoryLock) {
+            if (findDeviceStateForAudioDeviceAttributes(ada, ada.getType()) != null) {
+                return;
+            }
+            AdiDeviceState ads = new AdiDeviceState(
+                    ada.getType(), ada.getInternalType(), ada.getAddress());
+            mDeviceInventory.put(ads.getDeviceId(), ads);
         }
+        mDeviceBroker.persistAudioDeviceSettings();
     }
 
+    /**
+     * Finds the device state that matches the passed {@link AudioDeviceAttributes} and device
+     * type. Note: currently this method only returns a valid device for A2DP and BLE devices.
+     *
+     * @param ada attributes of device to match
+     * @param canonicalDeviceType external device type to match
+     * @return the found {@link AdiDeviceState} matching a cached A2DP or BLE device or
+     *         {@code null} otherwise.
+     */
     AdiDeviceState findDeviceStateForAudioDeviceAttributes(AudioDeviceAttributes ada,
             int canonicalDeviceType) {
         final boolean isWireless = isBluetoothDevice(ada.getInternalType());
-
         synchronized (mDeviceInventoryLock) {
-            for (AdiDeviceState deviceSetting : mDeviceInventory) {
-                if (deviceSetting.getDeviceType() == canonicalDeviceType
+            for (AdiDeviceState deviceState : mDeviceInventory.values()) {
+                if (deviceState.getDeviceType() == canonicalDeviceType
                         && (!isWireless || ada.getAddress().equals(
-                        deviceSetting.getDeviceAddress()))) {
-                    return deviceSetting;
+                        deviceState.getDeviceAddress()))) {
+                    return deviceState;
                 }
             }
         }
@@ -308,7 +338,7 @@ public String toString() {
                     + " devices:" + devices); });
         pw.println("\ndevices:\n");
         synchronized (mDeviceInventoryLock) {
-            for (AdiDeviceState device : mDeviceInventory) {
+            for (AdiDeviceState device : mDeviceInventory.values()) {
                 pw.println("\t" + device + "\n");
             }
         }
@@ -695,8 +725,8 @@ void onSetBtActiveDevice(@NonNull AudioDeviceBroker.BtDeviceInfo btInfo, int str
     }
 
     /*package*/ void registerStrategyPreferredDevicesDispatcher(
-            @NonNull IStrategyPreferredDevicesDispatcher dispatcher) {
-        mPrefDevDispatchers.register(dispatcher);
+            @NonNull IStrategyPreferredDevicesDispatcher dispatcher, boolean isPrivileged) {
+        mPrefDevDispatchers.register(dispatcher, isPrivileged);
     }
 
     /*package*/ void unregisterStrategyPreferredDevicesDispatcher(
@@ -730,8 +760,8 @@ void onSetBtActiveDevice(@NonNull AudioDeviceBroker.BtDeviceInfo btInfo, int str
     }
 
     /*package*/ void registerCapturePresetDevicesRoleDispatcher(
-            @NonNull ICapturePresetDevicesRoleDispatcher dispatcher) {
-        mDevRoleCapturePresetDispatchers.register(dispatcher);
+            @NonNull ICapturePresetDevicesRoleDispatcher dispatcher, boolean isPrivileged) {
+        mDevRoleCapturePresetDispatchers.register(dispatcher, isPrivileged);
     }
 
     /*package*/ void unregisterCapturePresetDevicesRoleDispatcher(
@@ -809,6 +839,9 @@ public boolean isDeviceConnected(@NonNull AudioDeviceAttributes device) {
                 mConnectedDevices.put(deviceKey, new DeviceInfo(
                         device, deviceName, address, AudioSystem.AUDIO_FORMAT_DEFAULT));
                 mDeviceBroker.postAccessoryPlugMediaUnmute(device);
+                if (AudioSystem.isBluetoothScoDevice(device)) {
+                    addAudioDeviceInInventoryIfNeeded(attributes);
+                }
                 mmi.set(MediaMetrics.Property.STATE, MediaMetrics.Value.CONNECTED).record();
                 return true;
             } else if (!connect && isConnected) {
@@ -1038,8 +1071,9 @@ private void makeA2dpDeviceAvailable(String address, String name, String eventSo
         mDeviceBroker.setBluetoothA2dpOnInt(true, true /*fromA2dp*/, eventSource);
         // at this point there could be another A2DP device already connected in APM, but it
         // doesn't matter as this new one will overwrite the previous one
-        final int res = mAudioSystem.setDeviceConnectionState(new AudioDeviceAttributes(
-                AudioSystem.DEVICE_OUT_BLUETOOTH_A2DP, address, name),
+        AudioDeviceAttributes ada = new AudioDeviceAttributes(
+                AudioSystem.DEVICE_OUT_BLUETOOTH_A2DP, address, name);
+        final int res = mAudioSystem.setDeviceConnectionState(ada,
                 AudioSystem.DEVICE_STATE_AVAILABLE, a2dpCodec);
 
         // TODO: log in MediaMetrics once distinction between connection failure and
@@ -1061,8 +1095,7 @@ private void makeA2dpDeviceAvailable(String address, String name, String eventSo
         // The convention for head tracking sensors associated with A2DP devices is to
         // use a UUID derived from the MAC address as follows:
         //   time_low = 0, time_mid = 0, time_hi = 0, clock_seq = 0, node = MAC Address
-        UUID sensorUuid = UuidUtils.uuidFromAudioDeviceAttributes(
-                new AudioDeviceAttributes(AudioSystem.DEVICE_OUT_BLUETOOTH_A2DP, address));
+        UUID sensorUuid = UuidUtils.uuidFromAudioDeviceAttributes(ada);
         final DeviceInfo di = new DeviceInfo(AudioSystem.DEVICE_OUT_BLUETOOTH_A2DP, name,
                 address, a2dpCodec, sensorUuid);
         final String diKey = di.getKey();
@@ -1073,8 +1106,10 @@ private void makeA2dpDeviceAvailable(String address, String name, String eventSo
 
         mDeviceBroker.postAccessoryPlugMediaUnmute(AudioSystem.DEVICE_OUT_BLUETOOTH_A2DP);
         setCurrentAudioRouteNameIfPossible(name, true /*fromA2dp*/);
+        addAudioDeviceInInventoryIfNeeded(ada);
     }
 
+
     @GuardedBy("mDevicesLock")
     private void makeA2dpDeviceUnavailableNow(String address, int a2dpCodec) {
         MediaMetrics.Item mmi = new MediaMetrics.Item(mMetricsId + "a2dp." + address)
@@ -1168,9 +1203,9 @@ private void makeHearingAidDeviceAvailable(
         final int hearingAidVolIndex = mDeviceBroker.getVssVolumeForDevice(streamType,
                 AudioSystem.DEVICE_OUT_HEARING_AID);
         mDeviceBroker.postSetHearingAidVolumeIndex(hearingAidVolIndex, streamType);
-
-        mAudioSystem.setDeviceConnectionState(new AudioDeviceAttributes(
-                AudioSystem.DEVICE_OUT_HEARING_AID, address, name),
+        AudioDeviceAttributes ada = new AudioDeviceAttributes(
+                AudioSystem.DEVICE_OUT_HEARING_AID, address, name);
+        mAudioSystem.setDeviceConnectionState(ada,
                 AudioSystem.DEVICE_STATE_AVAILABLE,
                 AudioSystem.AUDIO_FORMAT_DEFAULT);
         mConnectedDevices.put(
@@ -1181,6 +1216,7 @@ private void makeHearingAidDeviceAvailable(
         mDeviceBroker.postApplyVolumeOnDevice(streamType,
                 AudioSystem.DEVICE_OUT_HEARING_AID, "makeHearingAidDeviceAvailable");
         setCurrentAudioRouteNameIfPossible(name, false /*fromA2dp*/);
+        addAudioDeviceInInventoryIfNeeded(ada);
         new MediaMetrics.Item(mMetricsId + "makeHearingAidDeviceAvailable")
                 .set(MediaMetrics.Property.ADDRESS, address != null ? address : "")
                 .set(MediaMetrics.Property.DEVICE,
@@ -1217,13 +1253,15 @@ private void makeLeAudioDeviceAvailable(String address, String name, int streamT
              */
             mDeviceBroker.setBluetoothA2dpOnInt(true, false /*fromA2dp*/, eventSource);
 
-            AudioSystem.setDeviceConnectionState(new AudioDeviceAttributes(device, address, name),
+            AudioDeviceAttributes ada = new AudioDeviceAttributes(device, address, name);
+            AudioSystem.setDeviceConnectionState(ada,
                     AudioSystem.DEVICE_STATE_AVAILABLE,
                     AudioSystem.AUDIO_FORMAT_DEFAULT);
             mConnectedDevices.put(DeviceInfo.makeDeviceListKey(device, address),
                     new DeviceInfo(device, name, address, AudioSystem.AUDIO_FORMAT_DEFAULT));
             mDeviceBroker.postAccessoryPlugMediaUnmute(device);
             setCurrentAudioRouteNameIfPossible(name, /*fromA2dp=*/false);
+            addAudioDeviceInInventoryIfNeeded(ada);
         }
 
         if (streamType == AudioSystem.STREAM_DEFAULT) {
@@ -1524,6 +1562,9 @@ private void dispatchPreferredDevice(int strategy,
         final int nbDispatchers = mPrefDevDispatchers.beginBroadcast();
         for (int i = 0; i < nbDispatchers; i++) {
             try {
+                if (!((Boolean) mPrefDevDispatchers.getBroadcastCookie(i))) {
+                    devices = mDeviceBroker.anonymizeAudioDeviceAttributesListUnchecked(devices);
+                }
                 mPrefDevDispatchers.getBroadcastItem(i).dispatchPrefDevicesChanged(
                         strategy, devices);
             } catch (RemoteException e) {
@@ -1537,6 +1578,9 @@ private void dispatchDevicesRoleForCapturePreset(
         final int nbDispatchers = mDevRoleCapturePresetDispatchers.beginBroadcast();
         for (int i = 0; i < nbDispatchers; ++i) {
             try {
+                if (!((Boolean) mDevRoleCapturePresetDispatchers.getBroadcastCookie(i))) {
+                    devices = mDeviceBroker.anonymizeAudioDeviceAttributesListUnchecked(devices);
+                }
                 mDevRoleCapturePresetDispatchers.getBroadcastItem(i).dispatchDevicesRoleChanged(
                         capturePreset, role, devices);
             } catch (RemoteException e) {
@@ -1561,19 +1605,20 @@ UUID getDeviceSensorUuid(AudioDeviceAttributes device) {
         int deviceCatalogSize = 0;
         synchronized (mDeviceInventoryLock) {
             deviceCatalogSize = mDeviceInventory.size();
-        }
-        final StringBuilder settingsBuilder = new StringBuilder(
+
+            final StringBuilder settingsBuilder = new StringBuilder(
                 deviceCatalogSize * AdiDeviceState.getPeristedMaxSize());
 
-        synchronized (mDeviceInventoryLock) {
-            for (int i = 0; i < mDeviceInventory.size(); i++) {
-                settingsBuilder.append(mDeviceInventory.get(i).toPersistableString());
-                if (i != mDeviceInventory.size() - 1) {
-                    settingsBuilder.append(SETTING_DEVICE_SEPARATOR_CHAR);
-                }
+            Iterator<AdiDeviceState> iterator = mDeviceInventory.values().iterator();
+            if (iterator.hasNext()) {
+                settingsBuilder.append(iterator.next().toPersistableString());
+            }
+            while (iterator.hasNext()) {
+                settingsBuilder.append(SETTING_DEVICE_SEPARATOR_CHAR);
+                settingsBuilder.append(iterator.next().toPersistableString());
             }
+            return settingsBuilder.toString();
         }
-        return settingsBuilder.toString();
     }
 
     /*package*/ void setDeviceSettings(String settings) {