From c300a01bf49eb22a4a40fe9553380c0ed331197c Mon Sep 17 00:00:00 2001
From: Eric Biggers <ebiggers@google.com>
Date: Tue, 11 Jan 2022 17:01:22 -0800
Subject: [PATCH] Remove FDE support from accessibility settings

With FDE (Full Disk Encryption), secure start-up (i.e. requiring a PIN /
pattern / password to boot the device) was incompatible with
accessibility services.  Thus, the accessibility settings would ask the
user to disable secure start-up when enabling an accessibility service.

Now that FDE support has been removed in favor of FBE (File Based
Encryption), this is no longer necessary.  Remove it.

Bug: 208476087
Change-Id: I5f6e512f223df63e1b4d1c181fc8b3fe683dcd5f
(cherry picked from commit b4060ef65b69723ed1bf2411dfe0b928fe062958)
Merged-In: I5f6e512f223df63e1b4d1c181fc8b3fe683dcd5f
---
 ...e_accessibility_service_dialog_content.xml |  8 ---
 res/values/strings.xml                        | 24 -------
 .../AccessibilityServiceWarning.java          | 22 ------
 ...ccessibilityServicePreferenceFragment.java | 69 ++-----------------
 .../settings/password/ChooseLockGeneric.java  | 30 --------
 5 files changed, 4 insertions(+), 149 deletions(-)

diff --git a/res/layout/enable_accessibility_service_dialog_content.xml b/res/layout/enable_accessibility_service_dialog_content.xml
index 6b3220bc13e..3fe932cd12a 100644
--- a/res/layout/enable_accessibility_service_dialog_content.xml
+++ b/res/layout/enable_accessibility_service_dialog_content.xml
@@ -42,14 +42,6 @@
                 android:id="@+id/permissionDialog_title"
                 style="@style/AccessibilityDialogTitle" />
 
-            <TextView
-                android:id="@+id/encryption_warning"
-                android:layout_width="fill_parent"
-                android:layout_height="wrap_content"
-                android:padding="10dip"
-                android:textAlignment="viewStart"
-                android:textAppearance="?android:attr/textAppearanceMedium"/>
-
             <TextView
                 android:id="@+id/permissionDialog_description"
                 android:text="@string/accessibility_service_warning_description"
diff --git a/res/values/strings.xml b/res/values/strings.xml
index 73a3d3c7935..5042302d8aa 100644
--- a/res/values/strings.xml
+++ b/res/values/strings.xml
@@ -5704,30 +5704,6 @@
          can't verify user consent. [CHAR LIMIT=NONE] -->
     <string name="touch_filtered_warning">Because an app is obscuring a permission request, Settings
         can’t verify your response.</string>
-    <!-- Warning that the device data will not be encrypted with password or PIN if
-        enabling an accessibility service and there is a secure lock setup. [CHAR LIMIT=NONE] -->
-    <string name="enable_service_encryption_warning">If you turn on <xliff:g id="service"
-        example="TalkBack">%1$s</xliff:g>, your device won’t use your screen lock to enhance
-        data encryption.</string>
-    <!-- Warning that the device data will not be encrypted with password or PIN if
-         choosing a secure lock and there is an enabled accessibility service. [CHAR LIMIT=NONE] -->
-    <string name="secure_lock_encryption_warning">Because you\u2019ve turned on an accessibility service,
-        your device won’t use your screen lock to enhance data encryption.</string>
-
-    <!-- Message to the users to enter their pattern before enabling an accessibility service. [CHAR LIMIT=NONE] -->
-    <string name="enable_service_pattern_reason">Because turning on <xliff:g id="service"
-        example="TalkBack">%1$s</xliff:g> affects data encryption, you need to confirm your pattern.
-    </string>
-
-    <!-- Message to the users to enter their PIN before enabling an accessibility service. [CHAR LIMIT=NONE] -->
-    <string name="enable_service_pin_reason">Because turning on <xliff:g id="service"
-        example="TalkBack">%1$s</xliff:g> affects data encryption, you need to confirm your PIN.
-    </string>
-
-    <!-- Message to the users to enter their password before enabling an accessibility service. [CHAR LIMIT=NONE] -->
-    <string name="enable_service_password_reason">Because turning on <xliff:g id="service"
-        example="TalkBack">%1$s</xliff:g> affects data encryption, you need to confirm your password.
-    </string>
 
     <!-- Warning that explains that accessibility services have a lot of access to user data [CHAR LIMIT=NONE] -->
     <string name="accessibility_service_warning"><xliff:g id="service"
diff --git a/src/com/android/settings/accessibility/AccessibilityServiceWarning.java b/src/com/android/settings/accessibility/AccessibilityServiceWarning.java
index dcf78977c74..93ec8030b9e 100644
--- a/src/com/android/settings/accessibility/AccessibilityServiceWarning.java
+++ b/src/com/android/settings/accessibility/AccessibilityServiceWarning.java
@@ -23,7 +23,6 @@ import android.app.Dialog;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.graphics.drawable.Drawable;
-import android.os.storage.StorageManager;
 import android.text.BidiFormatter;
 import android.view.LayoutInflater;
 import android.view.MotionEvent;
@@ -86,16 +85,6 @@ public class AccessibilityServiceWarning {
         return ad;
     }
 
-    /**
-     * Returns whether the device is encrypted with legacy full disk encryption. Newer devices
-     * should be using File Based Encryption.
-     *
-     * @return true if device is encrypted
-     */
-    private static boolean isFullDiskEncrypted() {
-        return StorageManager.isNonDefaultBlockEncrypted();
-    }
-
     private static View createEnableDialogContentView(Context context,
             @NonNull AccessibilityServiceInfo info, View.OnClickListener listener,
             UninstallActionPerformer performer) {
@@ -105,17 +94,6 @@ public class AccessibilityServiceWarning {
         View content = inflater.inflate(R.layout.enable_accessibility_service_dialog_content,
                 null);
 
-        TextView encryptionWarningView = (TextView) content.findViewById(
-                R.id.encryption_warning);
-        if (isFullDiskEncrypted()) {
-            String text = context.getString(R.string.enable_service_encryption_warning,
-                    getServiceName(context, info));
-            encryptionWarningView.setText(text);
-            encryptionWarningView.setVisibility(View.VISIBLE);
-        } else {
-            encryptionWarningView.setVisibility(View.GONE);
-        }
-
         final Drawable icon;
         if (info.getResolveInfo().getIconResource() == 0) {
             icon = ContextCompat.getDrawable(context, R.drawable.ic_accessibility_generic);
diff --git a/src/com/android/settings/accessibility/ToggleAccessibilityServicePreferenceFragment.java b/src/com/android/settings/accessibility/ToggleAccessibilityServicePreferenceFragment.java
index bd634065103..6dd12175238 100644
--- a/src/com/android/settings/accessibility/ToggleAccessibilityServicePreferenceFragment.java
+++ b/src/com/android/settings/accessibility/ToggleAccessibilityServicePreferenceFragment.java
@@ -21,9 +21,7 @@ import static com.android.settings.accessibility.AccessibilityStatsLogUtils.logA
 import static com.android.settings.accessibility.PreferredShortcuts.retrieveUserShortcutType;
 
 import android.accessibilityservice.AccessibilityServiceInfo;
-import android.app.Activity;
 import android.app.Dialog;
-import android.app.admin.DevicePolicyManager;
 import android.app.settings.SettingsEnums;
 import android.content.BroadcastReceiver;
 import android.content.ComponentName;
@@ -38,9 +36,6 @@ import android.content.pm.ServiceInfo;
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.Handler;
-import android.os.UserHandle;
-import android.os.storage.StorageManager;
-import android.provider.Settings;
 import android.text.TextUtils;
 import android.util.Log;
 import android.view.Menu;
@@ -51,11 +46,9 @@ import android.widget.Switch;
 
 import androidx.annotation.Nullable;
 
-import com.android.internal.widget.LockPatternUtils;
 import com.android.settings.R;
 import com.android.settings.accessibility.AccessibilityUtil.UserShortcutType;
 import com.android.settings.overlay.FeatureFactory;
-import com.android.settings.password.ConfirmDeviceCredentialActivity;
 import com.android.settingslib.accessibility.AccessibilityUtils;
 
 import java.util.List;
@@ -66,8 +59,6 @@ public class ToggleAccessibilityServicePreferenceFragment extends
         ToggleFeaturePreferenceFragment {
 
     private static final String TAG = "ToggleAccessibilityServicePreferenceFragment";
-    private static final int ACTIVITY_REQUEST_CONFIRM_CREDENTIAL_FOR_WEAKER_ENCRYPTION = 1;
-    private LockPatternUtils mLockPatternUtils;
     private AtomicBoolean mIsDialogShown = new AtomicBoolean(/* initialValue= */ false);
 
     private static final String EMPTY_STRING = "";
@@ -106,7 +97,6 @@ public class ToggleAccessibilityServicePreferenceFragment extends
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        mLockPatternUtils = new LockPatternUtils(getPrefContext());
     }
 
     @Override
@@ -243,33 +233,8 @@ public class ToggleAccessibilityServicePreferenceFragment extends
                 .contains(mComponentName);
     }
 
-    /**
-     * Return whether the device is encrypted with legacy full disk encryption. Newer devices
-     * should be using File Based Encryption.
-     *
-     * @return true if device is encrypted
-     */
-    private boolean isFullDiskEncrypted() {
-        return StorageManager.isNonDefaultBlockEncrypted();
-    }
-
     @Override
     public void onActivityResult(int requestCode, int resultCode, Intent data) {
-        if (requestCode == ACTIVITY_REQUEST_CONFIRM_CREDENTIAL_FOR_WEAKER_ENCRYPTION) {
-            if (resultCode == Activity.RESULT_OK) {
-                handleConfirmServiceEnabled(/* confirmed= */ true);
-                // The user confirmed that they accept weaker encryption when
-                // enabling the accessibility service, so change encryption.
-                // Since we came here asynchronously, check encryption again.
-                if (isFullDiskEncrypted()) {
-                    mLockPatternUtils.clearEncryptionPassword();
-                    Settings.Global.putInt(getContentResolver(),
-                            Settings.Global.REQUIRE_PASSWORD_TO_DECRYPT, 0);
-                }
-            } else {
-                handleConfirmServiceEnabled(/* confirmed= */ false);
-            }
-        }
     }
 
     private void registerPackageRemoveReceiver() {
@@ -321,23 +286,6 @@ public class ToggleAccessibilityServicePreferenceFragment extends
         onPreferenceToggled(mPreferenceKey, confirmed);
     }
 
-    private String createConfirmCredentialReasonMessage() {
-        int resId = R.string.enable_service_password_reason;
-        switch (mLockPatternUtils.getKeyguardStoredPasswordQuality(UserHandle.myUserId())) {
-            case DevicePolicyManager.PASSWORD_QUALITY_SOMETHING: {
-                resId = R.string.enable_service_pattern_reason;
-            }
-            break;
-            case DevicePolicyManager.PASSWORD_QUALITY_NUMERIC:
-            case DevicePolicyManager.PASSWORD_QUALITY_NUMERIC_COMPLEX: {
-                resId = R.string.enable_service_pin_reason;
-            }
-            break;
-        }
-        return getString(resId, getAccessibilityServiceInfo().getResolveInfo()
-                .loadLabel(getPackageManager()));
-    }
-
     @Override
     public void onSwitchChanged(Switch switchView, boolean isChecked) {
         if (isChecked != isAccessibilityServiceEnabled()) {
@@ -461,20 +409,11 @@ public class ToggleAccessibilityServicePreferenceFragment extends
     }
 
     private void onAllowButtonFromEnableToggleClicked() {
-        if (isFullDiskEncrypted()) {
-            final String title = createConfirmCredentialReasonMessage();
-            final Intent intent = ConfirmDeviceCredentialActivity.createIntent(title, /* details= */
-                    null);
-            startActivityForResult(intent,
-                    ACTIVITY_REQUEST_CONFIRM_CREDENTIAL_FOR_WEAKER_ENCRYPTION);
-        } else {
-            handleConfirmServiceEnabled(/* confirmed= */ true);
-            if (isServiceSupportAccessibilityButton()) {
-                mIsDialogShown.set(false);
-                showPopupDialog(DialogEnums.LAUNCH_ACCESSIBILITY_TUTORIAL);
-            }
+        handleConfirmServiceEnabled(/* confirmed= */ true);
+        if (isServiceSupportAccessibilityButton()) {
+            mIsDialogShown.set(false);
+            showPopupDialog(DialogEnums.LAUNCH_ACCESSIBILITY_TUTORIAL);
         }
-
         mDialog.dismiss();
     }
 
diff --git a/src/com/android/settings/password/ChooseLockGeneric.java b/src/com/android/settings/password/ChooseLockGeneric.java
index a1826ba0cbc..2d6f6b0278d 100644
--- a/src/com/android/settings/password/ChooseLockGeneric.java
+++ b/src/com/android/settings/password/ChooseLockGeneric.java
@@ -614,7 +614,6 @@ public class ChooseLockGeneric extends SettingsActivity {
                 disableUnusablePreferences();
                 updatePreferenceText();
                 updateCurrentPreference();
-                updatePreferenceSummaryIfNeeded();
             } else if (!isRecreatingActivity) {
                 // Don't start the activity again if we are recreated for configuration change
                 updateUnlockMethodAndFinish(quality, false, true /* chooseLockSkipped */);
@@ -715,13 +714,6 @@ public class ChooseLockGeneric extends SettingsActivity {
             }
         }
 
-        private void setPreferenceSummary(ScreenLockType lock, @StringRes int summary) {
-            Preference preference = findPreference(lock.preferenceKey);
-            if (preference != null) {
-                preference.setSummary(summary);
-            }
-        }
-
         private void updateCurrentPreference() {
             String currentKey = getKeyForCurrent();
             Preference preference = findPreference(currentKey);
@@ -764,28 +756,6 @@ public class ChooseLockGeneric extends SettingsActivity {
             }
         }
 
-        private void updatePreferenceSummaryIfNeeded() {
-            // On a default block encrypted device with accessibility, add a warning
-            // that your data is not credential encrypted
-            if (!StorageManager.isBlockEncrypted()) {
-                return;
-            }
-
-            if (StorageManager.isNonDefaultBlockEncrypted()) {
-                return;
-            }
-
-            if (AccessibilityManager.getInstance(getActivity()).getEnabledAccessibilityServiceList(
-                    AccessibilityServiceInfo.FEEDBACK_ALL_MASK).isEmpty()) {
-                return;
-            }
-
-            setPreferenceSummary(ScreenLockType.PATTERN, R.string.secure_lock_encryption_warning);
-            setPreferenceSummary(ScreenLockType.PIN, R.string.secure_lock_encryption_warning);
-            setPreferenceSummary(ScreenLockType.PASSWORD, R.string.secure_lock_encryption_warning);
-            setPreferenceSummary(ScreenLockType.MANAGED, R.string.secure_lock_encryption_warning);
-        }
-
         protected Intent getLockManagedPasswordIntent(LockscreenCredential password) {
             return mManagedPasswordProvider.createIntent(false, password);
         }