Add the clearCredentialSession api to CredentialManager.

This api is similar to the web preventSilentAccess api that clears the
user credential session to prevent future automatic sign-in.

Test: local deployment
Bug: 256848673
Change-Id: I510fd0160d5689ef396fbf1078c42c0e1b643669

4 files changed, 111 insertions, 8 deletions

diff --git a/core/java/android/credentials/CredentialManager.java b/core/java/android/credentials/CredentialManager.java
index 30ee118d3b59..c9a0626341b7 100644
--- a/core/java/android/credentials/CredentialManager.java
+++ b/core/java/android/credentials/CredentialManager.java
@@ -62,10 +62,10 @@ public final class CredentialManager {
      * <p>The execution can potentially launch UI flows to collect user consent to using a
      * credential, display a picker when multiple credentials exist, etc.
      *
-     * @param request the request specifying type(s) of credentials to get from the user.
-     * @param cancellationSignal an optional signal that allows for cancelling this call.
-     * @param executor the callback will take place on this {@link Executor}.
-     * @param callback the callback invoked when the request succeeds or fails.
+     * @param request the request specifying type(s) of credentials to get from the user
+     * @param cancellationSignal an optional signal that allows for cancelling this call
+     * @param executor the callback will take place on this {@link Executor}
+     * @param callback the callback invoked when the request succeeds or fails
      */
     public void executeGetCredential(
             @NonNull GetCredentialRequest request,
@@ -101,10 +101,10 @@ public final class CredentialManager {
      * <p>The execution can potentially launch UI flows to collect user consent to creating
      * or storing the new credential, etc.
      *
-     * @param request the request specifying type(s) of credentials to get from the user.
-     * @param cancellationSignal an optional signal that allows for cancelling this call.
-     * @param executor the callback will take place on this {@link Executor}.
-     * @param callback the callback invoked when the request succeeds or fails.
+     * @param request the request specifying type(s) of credentials to get from the user
+     * @param cancellationSignal an optional signal that allows for cancelling this call
+     * @param executor the callback will take place on this {@link Executor}
+     * @param callback the callback invoked when the request succeeds or fails
      */
     public void executeCreateCredential(
             @NonNull CreateCredentialRequest request,
@@ -135,6 +135,44 @@ public final class CredentialManager {
         }
     }
 
+    /**
+     * Clears the current user credential session from all credential providers.
+     *
+     * <p>Usually invoked after your user signs out of your app so that they will not be
+     * automatically signed in the next time.
+     *
+     * @param cancellationSignal an optional signal that allows for cancelling this call
+     * @param executor the callback will take place on this {@link Executor}
+     * @param callback the callback invoked when the request succeeds or fails
+     *
+     * @hide
+     */
+    public void clearCredentialSession(
+            @Nullable CancellationSignal cancellationSignal,
+            @CallbackExecutor @NonNull Executor executor,
+            @NonNull OutcomeReceiver<Void, CredentialManagerException> callback) {
+        requireNonNull(executor, "executor must not be null");
+        requireNonNull(callback, "callback must not be null");
+
+        if (cancellationSignal != null && cancellationSignal.isCanceled()) {
+            Log.w(TAG, "executeCreateCredential already canceled");
+            return;
+        }
+
+        ICancellationSignal cancelRemote = null;
+        try {
+            cancelRemote = mService.clearCredentialSession(
+                    new ClearCredentialSessionTransport(executor, callback),
+                    mContext.getOpPackageName());
+        } catch (RemoteException e) {
+            e.rethrowFromSystemServer();
+        }
+
+        if (cancellationSignal != null && cancelRemote != null) {
+            cancellationSignal.setRemote(cancelRemote);
+        }
+    }
+
     private static class GetCredentialTransport extends IGetCredentialCallback.Stub {
         // TODO: listen for cancellation to release callback.
 
@@ -184,4 +222,29 @@ public final class CredentialManager {
                     () -> mCallback.onError(new CredentialManagerException(errorCode, message)));
         }
     }
+
+    private static class ClearCredentialSessionTransport
+            extends IClearCredentialSessionCallback.Stub {
+        // TODO: listen for cancellation to release callback.
+
+        private final Executor mExecutor;
+        private final OutcomeReceiver<Void, CredentialManagerException> mCallback;
+
+        private ClearCredentialSessionTransport(Executor executor,
+                OutcomeReceiver<Void, CredentialManagerException> callback) {
+            mExecutor = executor;
+            mCallback = callback;
+        }
+
+        @Override
+        public void onSuccess() {
+            mCallback.onResult(null);
+        }
+
+        @Override
+        public void onError(int errorCode, String message) {
+            mExecutor.execute(
+                    () -> mCallback.onError(new CredentialManagerException(errorCode, message)));
+        }
+    }
 }
diff --git a/core/java/android/credentials/IClearCredentialSessionCallback.aidl b/core/java/android/credentials/IClearCredentialSessionCallback.aidl
new file mode 100644
index 000000000000..903e7f56cd2e
--- /dev/null
+++ b/core/java/android/credentials/IClearCredentialSessionCallback.aidl
@@ -0,0 +1,27 @@
+/*
+ * Copyright 2022 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 android.credentials;
+
+/**
+ * Listener for clearCredentialSession request.
+ *
+ * @hide
+ */
+interface IClearCredentialSessionCallback {
+    oneway void onSuccess();
+    oneway void onError(int errorCode, String message);
+}
\ No newline at end of file
diff --git a/core/java/android/credentials/ICredentialManager.aidl b/core/java/android/credentials/ICredentialManager.aidl
index b0f27f9164f3..35688d7fe113 100644
--- a/core/java/android/credentials/ICredentialManager.aidl
+++ b/core/java/android/credentials/ICredentialManager.aidl
@@ -18,6 +18,7 @@ package android.credentials;
 
 import android.credentials.CreateCredentialRequest;
 import android.credentials.GetCredentialRequest;
+import android.credentials.IClearCredentialSessionCallback;
 import android.credentials.ICreateCredentialCallback;
 import android.credentials.IGetCredentialCallback;
 import android.os.ICancellationSignal;
@@ -32,4 +33,6 @@ interface ICredentialManager {
     @nullable ICancellationSignal executeGetCredential(in GetCredentialRequest request, in IGetCredentialCallback callback, String callingPackage);
 
     @nullable ICancellationSignal executeCreateCredential(in CreateCredentialRequest request, in ICreateCredentialCallback callback, String callingPackage);
+
+    @nullable ICancellationSignal clearCredentialSession(in IClearCredentialSessionCallback callback, String callingPackage);
 }
diff --git a/services/credentials/java/com/android/server/credentials/CredentialManagerService.java b/services/credentials/java/com/android/server/credentials/CredentialManagerService.java
index 40412db2ed5e..321f022f526f 100644
--- a/services/credentials/java/com/android/server/credentials/CredentialManagerService.java
+++ b/services/credentials/java/com/android/server/credentials/CredentialManagerService.java
@@ -24,6 +24,7 @@ import android.content.Context;
 import android.content.pm.PackageManager;
 import android.credentials.CreateCredentialRequest;
 import android.credentials.GetCredentialRequest;
+import android.credentials.IClearCredentialSessionCallback;
 import android.credentials.ICreateCredentialCallback;
 import android.credentials.ICredentialManager;
 import android.credentials.IGetCredentialCallback;
@@ -155,5 +156,14 @@ public final class CredentialManagerService extends
             ICancellationSignal cancelTransport = CancellationSignal.createTransport();
             return cancelTransport;
         }
+
+        @Override
+        public ICancellationSignal clearCredentialSession(
+                IClearCredentialSessionCallback callback, String callingPackage) {
+            // TODO: implement.
+            Log.i(TAG, "clearCredentialSession");
+            ICancellationSignal cancelTransport = CancellationSignal.createTransport();
+            return cancelTransport;
+        }
     }
 }