| /* |
| * Copyright (C) 2020 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.server.biometrics.sensors; |
| |
| import static com.android.internal.annotations.VisibleForTesting.Visibility; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.content.Context; |
| import android.hardware.biometrics.BiometricConstants; |
| import android.os.IBinder; |
| import android.os.RemoteException; |
| import android.util.Slog; |
| |
| import com.android.internal.annotations.VisibleForTesting; |
| import com.android.server.biometrics.log.BiometricContext; |
| import com.android.server.biometrics.log.BiometricLogger; |
| |
| import java.util.NoSuchElementException; |
| |
| /** |
| * Abstract base class for keeping track and dispatching events from the biometric's HAL to |
| * the current client. Subclasses are responsible for coordinating the interaction with |
| * the biometric's HAL for the specific action (e.g. authenticate, enroll, enumerate, etc.). |
| */ |
| public abstract class BaseClientMonitor implements IBinder.DeathRecipient { |
| |
| private static final String TAG = "BaseClientMonitor"; |
| protected static final boolean DEBUG = true; |
| |
| // Counter used to distinguish between ClientMonitor instances to help debugging. |
| private static int sCount = 0; |
| |
| private final int mSequentialId; |
| @NonNull private final Context mContext; |
| private final int mTargetUserId; |
| @NonNull private final String mOwner; |
| private final int mSensorId; // sensorId as configured by the framework |
| @NonNull private final BiometricLogger mLogger; |
| @NonNull private final BiometricContext mBiometricContext; |
| |
| @Nullable private IBinder mToken; |
| private long mRequestId; |
| @Nullable private ClientMonitorCallbackConverter mListener; |
| // Currently only used for authentication client. The cookie generated by BiometricService |
| // is never 0. |
| private final int mCookie; |
| private boolean mAlreadyDone = false; |
| |
| // Use an empty callback by default since delayed operations can receive events |
| // before they are started and cause NPE in subclasses that access this field directly. |
| @NonNull protected ClientMonitorCallback mCallback = new ClientMonitorCallback() { |
| @Override |
| public void onClientStarted(@NonNull BaseClientMonitor clientMonitor) { |
| Slog.e(TAG, "mCallback onClientStarted: called before set (should not happen)"); |
| } |
| |
| @Override |
| public void onClientFinished(@NonNull BaseClientMonitor clientMonitor, |
| boolean success) { |
| Slog.e(TAG, "mCallback onClientFinished: called before set (should not happen)"); |
| } |
| }; |
| |
| /** |
| * @param context system_server context |
| * @param token a unique token for the client |
| * @param listener recipient of related events (e.g. authentication) |
| * @param userId target user id for operation |
| * @param owner name of the client that owns this |
| * @param cookie BiometricPrompt authentication cookie (to be moved into a subclass soon) |
| * @param sensorId ID of the sensor that the operation should be requested of |
| * @param logger framework stats logger |
| * @param biometricContext system context metadata |
| */ |
| public BaseClientMonitor(@NonNull Context context, |
| @Nullable IBinder token, @Nullable ClientMonitorCallbackConverter listener, int userId, |
| @NonNull String owner, int cookie, int sensorId, |
| @NonNull BiometricLogger logger, @NonNull BiometricContext biometricContext) { |
| mSequentialId = sCount++; |
| mContext = context; |
| mToken = token; |
| mRequestId = -1; |
| mListener = listener; |
| mTargetUserId = userId; |
| mOwner = owner; |
| mCookie = cookie; |
| mSensorId = sensorId; |
| mLogger = logger; |
| mBiometricContext = biometricContext; |
| |
| try { |
| if (token != null) { |
| token.linkToDeath(this, 0); |
| } |
| } catch (RemoteException e) { |
| Slog.w(TAG, "caught remote exception in linkToDeath: ", e); |
| } |
| } |
| |
| /** A ClientMonitorEnum constant defined in biometrics.proto */ |
| public abstract int getProtoEnum(); |
| |
| /** True if the ClientMonitor should cancel any current and pending interruptable clients. */ |
| public boolean interruptsPrecedingClients() { |
| return false; |
| } |
| |
| /** |
| * Sets the lifecycle callback before the operation is started via |
| * {@link #start(ClientMonitorCallback)} when the client must wait for a cookie before starting. |
| * |
| * @param callback lifecycle callback (typically same callback used for starting the operation) |
| */ |
| public void waitForCookie(@NonNull ClientMonitorCallback callback) { |
| mCallback = callback; |
| } |
| |
| /** |
| * Starts the ClientMonitor's lifecycle. |
| * @param callback invoked when the operation is complete (succeeds, fails, etc.) |
| */ |
| public void start(@NonNull ClientMonitorCallback callback) { |
| mCallback = wrapCallbackForStart(callback); |
| mCallback.onClientStarted(this); |
| } |
| |
| /** |
| * Called during start to provide subclasses a hook for decorating the callback. |
| * |
| * Returns the original callback unless overridden. |
| */ |
| @NonNull |
| protected ClientMonitorCallback wrapCallbackForStart(@NonNull ClientMonitorCallback callback) { |
| return callback; |
| } |
| |
| /** Signals this operation has completed its lifecycle and should no longer be used. */ |
| @VisibleForTesting(visibility = Visibility.PACKAGE) |
| public void destroy() { |
| mAlreadyDone = true; |
| if (mToken != null) { |
| try { |
| mToken.unlinkToDeath(this, 0); |
| } catch (NoSuchElementException e) { |
| // TODO: remove when duplicate call bug is found |
| Slog.e(TAG, "destroy(): " + this + ":", new Exception("here")); |
| } |
| mToken = null; |
| } |
| } |
| |
| /** |
| * Call while the operation is still active, but nearly done, to prevent any action |
| * upon client death (only needed for authentication clients). |
| */ |
| void markAlreadyDone() { |
| Slog.d(TAG, "marking operation as done: " + this); |
| mAlreadyDone = true; |
| } |
| |
| /** If this operation has been marked as completely done (or cancelled). */ |
| public boolean isAlreadyDone() { |
| return mAlreadyDone; |
| } |
| |
| @Override |
| public void binderDied() { |
| binderDiedInternal(true /* clearListener */); |
| } |
| |
| // TODO(b/157790417): Move this to the scheduler |
| void binderDiedInternal(boolean clearListener) { |
| Slog.e(TAG, "Binder died, operation: " + this); |
| |
| if (mAlreadyDone) { |
| Slog.w(TAG, "Binder died but client is finished, ignoring"); |
| return; |
| } |
| |
| // If the current client dies we should cancel the current operation. |
| if (this.isInterruptable()) { |
| Slog.e(TAG, "Binder died, cancelling client"); |
| this.cancel(); |
| } |
| mToken = null; |
| if (clearListener) { |
| mListener = null; |
| } |
| } |
| |
| /** |
| * Only valid for AuthenticationClient. |
| * @return true if the client is authenticating for a crypto operation. |
| */ |
| protected boolean isCryptoOperation() { |
| return false; |
| } |
| |
| /** System context that may change during operations. */ |
| @NonNull |
| protected BiometricContext getBiometricContext() { |
| return mBiometricContext; |
| } |
| |
| /** Logger for this client */ |
| @NonNull |
| public BiometricLogger getLogger() { |
| return mLogger; |
| } |
| |
| @NonNull |
| public final Context getContext() { |
| return mContext; |
| } |
| |
| @NonNull |
| public final String getOwnerString() { |
| return mOwner; |
| } |
| |
| @Nullable |
| public final ClientMonitorCallbackConverter getListener() { |
| return mListener; |
| } |
| |
| public int getTargetUserId() { |
| return mTargetUserId; |
| } |
| |
| @Nullable |
| public final IBinder getToken() { |
| return mToken; |
| } |
| |
| public int getSensorId() { |
| return mSensorId; |
| } |
| |
| /** Cookie set when this monitor was created. */ |
| public int getCookie() { |
| return mCookie; |
| } |
| |
| /** Unique request id. */ |
| public long getRequestId() { |
| return mRequestId; |
| } |
| |
| /** If a unique id has been set via {@link #setRequestId(long)} */ |
| public boolean hasRequestId() { |
| return mRequestId > 0; |
| } |
| |
| /** |
| * A unique identifier used to tie this operation to a request (i.e an API invocation). |
| * |
| * Subclasses should not call this method if this operation does not have a direct |
| * correspondence to a request and {@link #hasRequestId()} will return false. |
| */ |
| protected final void setRequestId(long id) { |
| if (id <= 0) { |
| throw new IllegalArgumentException("request id must be positive"); |
| } |
| mRequestId = id; |
| } |
| |
| @VisibleForTesting |
| public ClientMonitorCallback getCallback() { |
| return mCallback; |
| } |
| |
| @Override |
| public String toString() { |
| return "{[" + mSequentialId + "] " |
| + this.getClass().getName() |
| + ", proto=" + getProtoEnum() |
| + ", owner=" + getOwnerString() |
| + ", cookie=" + getCookie() |
| + ", requestId=" + getRequestId() |
| + ", userId=" + getTargetUserId() + "}"; |
| } |
| |
| /** |
| * Cancels this ClientMonitor |
| */ |
| public void cancel() { |
| cancelWithoutStarting(mCallback); |
| } |
| |
| /** |
| * Cancels this ClientMonitor without starting |
| * @param callback |
| */ |
| public void cancelWithoutStarting(@NonNull ClientMonitorCallback callback) { |
| Slog.d(TAG, "cancelWithoutStarting: " + this); |
| |
| final int errorCode = BiometricConstants.BIOMETRIC_ERROR_CANCELED; |
| try { |
| ClientMonitorCallbackConverter listener = getListener(); |
| if (listener != null) { |
| listener.onError(getSensorId(), getCookie(), errorCode, 0 /* vendorCode */); |
| } |
| } catch (RemoteException e) { |
| Slog.w(TAG, "Failed to invoke sendError", e); |
| } |
| callback.onClientFinished(this, true /* success */); |
| } |
| |
| /** |
| * Checks if other client monitor can interrupt current client monitor |
| * @return if current client can be interrupted |
| */ |
| public boolean isInterruptable() { |
| return false; |
| } |
| } |