From 9b1d542985a84b094f8b8a8c698527b19e58a45a Mon Sep 17 00:00:00 2001
From: Beverly <beverlyt@google.com>
Date: Fri, 1 Sep 2017 11:14:03 -0400
Subject: [PATCH] DO NOT MERGE Backporting potential usb tapjacking precaution.

Bug: 62187985
Test: manual, backport
Change-Id: Id9fff28cf54969cbcbdc8a3bfaeadc02ff597c89
---
 packages/SystemUI/res/values/strings.xml      |  5 ++++
 .../systemui/usb/UsbDebuggingActivity.java    | 27 +++++++++++++++++++
 2 files changed, 32 insertions(+)

diff --git a/packages/SystemUI/res/values/strings.xml b/packages/SystemUI/res/values/strings.xml
index 3eac84fd4dcef..f391f69b99798 100644
--- a/packages/SystemUI/res/values/strings.xml
+++ b/packages/SystemUI/res/values/strings.xml
@@ -1120,4 +1120,9 @@
     <!-- Dialog asking if the tuner should really be removed from settings [CHAR LIMIT=NONE]-->
     <string name="remove_from_settings_prompt">Remove System UI Tuner from Settings and stop using all of its features?"</string>
 
+    <!-- Warning shown when user input has been blocked due to another app overlaying screen
+     content. Since we don't know what the app is showing on top of the input target, we
+     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>
 </resources>
diff --git a/packages/SystemUI/src/com/android/systemui/usb/UsbDebuggingActivity.java b/packages/SystemUI/src/com/android/systemui/usb/UsbDebuggingActivity.java
index f5447a293503f..59f6c20565243 100644
--- a/packages/SystemUI/src/com/android/systemui/usb/UsbDebuggingActivity.java
+++ b/packages/SystemUI/src/com/android/systemui/usb/UsbDebuggingActivity.java
@@ -31,8 +31,12 @@ import android.os.ServiceManager;
 import android.os.SystemProperties;
 import android.util.Log;
 import android.view.LayoutInflater;
+import android.view.MotionEvent;
 import android.view.View;
+import android.view.Window;
+import android.view.WindowManager;
 import android.widget.CheckBox;
+import android.widget.Toast;
 
 import com.android.internal.app.AlertActivity;
 import com.android.internal.app.AlertController;
@@ -48,6 +52,10 @@ public class UsbDebuggingActivity extends AlertActivity
 
     @Override
     public void onCreate(Bundle icicle) {
+        Window window = getWindow();
+        window.addPrivateFlags(WindowManager.LayoutParams.PRIVATE_FLAG_HIDE_NON_SYSTEM_OVERLAY_WINDOWS);
+        window.setType(WindowManager.LayoutParams.TYPE_SYSTEM_DIALOG);
+
         super.onCreate(icicle);
 
         if (SystemProperties.getInt("service.adb.tcp.port", 0) == 0) {
@@ -79,6 +87,25 @@ public class UsbDebuggingActivity extends AlertActivity
         ap.mView = checkbox;
 
         setupAlert();
+
+        // adding touch listener on affirmative button - checks if window is obscured
+        // if obscured, do not let user give permissions (could be tapjacking involved)
+        final View.OnTouchListener filterTouchListener = new View.OnTouchListener() {
+            public boolean onTouch(View v, MotionEvent event) {
+                // Filter obscured touches by consuming them.
+                if (((event.getFlags() & MotionEvent.FLAG_WINDOW_IS_OBSCURED) != 0)
+                        || ((event.getFlags() & MotionEvent.FLAG_WINDOW_IS_PARTIALLY_OBSCURED) != 0)) {
+                    if (event.getAction() == MotionEvent.ACTION_UP) {
+                        Toast.makeText(v.getContext(),
+                                R.string.touch_filtered_warning,
+                                Toast.LENGTH_SHORT).show();
+                    }
+                    return true;
+                }
+                return false;
+            }
+        };
+        mAlert.getButton(BUTTON_POSITIVE).setOnTouchListener(filterTouchListener);
     }
 
     private class UsbDisconnectedReceiver extends BroadcastReceiver {