Added autofill test to check apps cannot bypass package name on AssistStructure

Test: cts-tradefed run commandAndExit cts-dev -m CtsAutoFillServiceTestCases -t android.autofillservice.cts.VirtualContainerActivityTest#testAppCannotFakePackageName

Bug: 69981710

Change-Id: I3abf999eb6056c1df7982780bae43b58337c0668
Merged-In: I3abf999eb6056c1df7982780bae43b58337c0668
(cherry picked from commit 48f34218c6ec41fd6137ee5a59b69e4b6e2e9cd7)

4 files changed, 98 insertions, 1 deletions

diff --git a/tests/autofillservice/src/android/autofillservice/cts/Helper.java b/tests/autofillservice/src/android/autofillservice/cts/Helper.java
index c1a70f09f53..f1d02dd12d1 100644
--- a/tests/autofillservice/src/android/autofillservice/cts/Helper.java
+++ b/tests/autofillservice/src/android/autofillservice/cts/Helper.java
@@ -45,6 +45,7 @@ import android.webkit.WebView;
 
 import com.android.compatibility.common.util.SystemUtil;
 
+import java.lang.reflect.Field;
 import java.util.List;
 import java.util.function.Function;
 
@@ -855,6 +856,50 @@ final class Helper {
         return InstrumentationRegistry.getInstrumentation().getContext();
     }
 
+    private static Field getField(Class<?> clazz, String fieldName) {
+        final Field[] fields = clazz.getDeclaredFields();
+        final StringBuilder fieldNames = new StringBuilder();
+        for (Field field : fields) {
+            fieldNames.append(field.getName()).append(" ");
+            field.setAccessible(true);
+            if (field.getName().equals(fieldName)) {
+                return field;
+            }
+        }
+        throw new IllegalArgumentException(
+                "no field " + fieldName + " on " + clazz.getName() + ": " + fieldNames);
+    }
+
+    /**
+     * Uses reflection to get a field from an object.
+     */
+    static <T> T getField(Object object, String fieldName) {
+        try {
+            final Class<?> clazz = object.getClass();
+            final Field field = getField(clazz, fieldName);
+            @SuppressWarnings("unchecked")
+            final T value = (T) field.get(object);
+            return value;
+        } catch (Exception e) {
+            throw new IllegalArgumentException(
+                    "error getting field " + fieldName + " from object" + object, e);
+        }
+    }
+
+    /**
+     * Uses reflection to set a field in an object.
+     */
+    static void setField(Object object, String fieldName, Object value) {
+        try {
+            final Class<?> clazz = object.getClass();
+            final Field field = getField(clazz, fieldName);
+            field.set(object, value);
+        } catch (Exception e) {
+            throw new IllegalArgumentException("error setting field " + fieldName + " on object "
+                    + object, e);
+        }
+    }
+
     /**
      * Cleans up the autofill state; should be called before pretty much any test.
      */
diff --git a/tests/autofillservice/src/android/autofillservice/cts/InstrumentedAutoFillService.java b/tests/autofillservice/src/android/autofillservice/cts/InstrumentedAutoFillService.java
index 2c234cdef5d..6694e5a145a 100644
--- a/tests/autofillservice/src/android/autofillservice/cts/InstrumentedAutoFillService.java
+++ b/tests/autofillservice/src/android/autofillservice/cts/InstrumentedAutoFillService.java
@@ -125,7 +125,8 @@ public class InstrumentedAutoFillService extends AutofillService {
         final ComponentName component = contexts.get(contexts.size() - 1).getStructure()
                 .getActivityComponent();
         final String actualPackage = component.getPackageName();
-        if (!actualPackage.equals(getPackageName())) {
+        if (!actualPackage.equals(getPackageName())
+                && !actualPackage.equals(sReplier.mAcceptedPackageName)) {
             Log.w(TAG, "Got request from package " + actualPackage);
             return false;
         }
@@ -246,16 +247,22 @@ public class InstrumentedAutoFillService extends AutofillService {
         private final BlockingQueue<SaveRequest> mSaveRequests = new LinkedBlockingQueue<>();
 
         private List<Exception> mExceptions;
+        private String mAcceptedPackageName;
 
         private Replier() {
         }
 
+
         private IdMode mIdMode = IdMode.RESOURCE_ID;
 
         public void setIdMode(IdMode mode) {
             this.mIdMode = mode;
         }
 
+        public void acceptRequestsFromPackage(String packageName) {
+            mAcceptedPackageName = packageName;
+        }
+
         /**
          * Gets the exceptions thrown asynchronously, if any.
          */
@@ -356,6 +363,7 @@ public class InstrumentedAutoFillService extends AutofillService {
             mFillRequests.clear();
             mSaveRequests.clear();
             mExceptions = null;
+            mAcceptedPackageName = null;
         }
 
         private void onFillRequest(List<FillContext> contexts, Bundle data,
diff --git a/tests/autofillservice/src/android/autofillservice/cts/VirtualContainerActivityTest.java b/tests/autofillservice/src/android/autofillservice/cts/VirtualContainerActivityTest.java
index 8adbdd7fe2d..31eae24ba6c 100644
--- a/tests/autofillservice/src/android/autofillservice/cts/VirtualContainerActivityTest.java
+++ b/tests/autofillservice/src/android/autofillservice/cts/VirtualContainerActivityTest.java
@@ -35,6 +35,7 @@ import android.app.assist.AssistStructure.ViewNode;
 import android.autofillservice.cts.CannedFillResponse.CannedDataset;
 import android.autofillservice.cts.InstrumentedAutoFillService.FillRequest;
 import android.autofillservice.cts.VirtualContainerView.Line;
+import android.content.ComponentName;
 import android.graphics.Rect;
 import android.os.SystemClock;
 import android.service.autofill.SaveInfo;
@@ -411,6 +412,30 @@ public class VirtualContainerActivityTest extends AutoFillServiceTestCase {
         sUiBot.assertSaveShowing(SAVE_DATA_TYPE_PASSWORD);
     }
 
+    @Test
+    public void testAppCannotFakePackageName() throws Exception {
+        // Set service.
+        enableService();
+
+        // Set expectations.
+        sReplier.acceptRequestsFromPackage("MALICIOUS");
+        mActivity.mCustomView.fakePackageName(new ComponentName("MALICIOUS", "AM.I"));
+        sReplier.addResponse(new CannedDataset.Builder()
+                .setField(ID_USERNAME, "dude")
+                .setField(ID_PASSWORD, "sweet")
+                .setPresentation(createPresentation("The Dude"))
+                .build());
+
+        // Trigger auto-fill.
+        mActivity.mUsername.changeFocus(true);
+        assertDatasetShown(mActivity.mUsername, "The Dude");
+
+        // Make sure package name was sanitized.
+        final FillRequest request = sReplier.getNextFillRequest();
+        assertThat(request.structure.getActivityComponent().getPackageName())
+                .isEqualTo(mPackageName);
+    }
+
     /**
      * Asserts the dataset picker is properly displayed in a give line.
      */
diff --git a/tests/autofillservice/src/android/autofillservice/cts/VirtualContainerView.java b/tests/autofillservice/src/android/autofillservice/cts/VirtualContainerView.java
index 205fcaef4a3..8eecc294796 100644
--- a/tests/autofillservice/src/android/autofillservice/cts/VirtualContainerView.java
+++ b/tests/autofillservice/src/android/autofillservice/cts/VirtualContainerView.java
@@ -20,7 +20,9 @@ import static android.autofillservice.cts.Helper.FILL_TIMEOUT_MS;
 
 import static com.google.common.truth.Truth.assertWithMessage;
 
+import android.app.assist.AssistStructure;
 import android.app.assist.AssistStructure.ViewNode;
+import android.content.ComponentName;
 import android.content.Context;
 import android.graphics.Canvas;
 import android.graphics.Color;
@@ -72,6 +74,7 @@ class VirtualContainerView extends View {
     private int mUnfocusedColor;
     private boolean mSync = true;
     private boolean mOverrideDispatchProvideAutofillStructure = false;
+    private ComponentName mFakedComponentName;
 
     public VirtualContainerView(Context context, AttributeSet attrs) {
         super(context, attrs);
@@ -192,6 +195,18 @@ class VirtualContainerView extends View {
         Log.d(TAG, "onProvideAutofillVirtualStructure(): flags = " + flags);
         super.onProvideAutofillVirtualStructure(structure, flags);
 
+        if (mFakedComponentName != null) {
+            Log.d(TAG, "Faking package name to " + mFakedComponentName);
+            try {
+                final AssistStructure assistStructure = Helper.getField(structure, "mAssist");
+                if (assistStructure != null) {
+                    Helper.setField(assistStructure, "mActivityComponent", mFakedComponentName);
+                }
+            } catch (Exception e) {
+                Log.e(TAG, "Could not fake package name to " + mFakedComponentName, e);
+            }
+        }
+
         final String packageName = getContext().getPackageName();
         structure.setClassName(getClass().getName());
         final int childrenSize = mItems.size();
@@ -254,6 +269,10 @@ class VirtualContainerView extends View {
         mSync = sync;
     }
 
+    void fakePackageName(ComponentName name) {
+        mFakedComponentName = name;
+    }
+
     void setOverrideDispatchProvideAutofillStructure(boolean flag) {
         mOverrideDispatchProvideAutofillStructure = flag;
     }