From 6ada12749c9dab3e813fbdbebe527cd47e6a7f57 Mon Sep 17 00:00:00 2001
From: Prabir Pradhan <prabirmsp@google.com>
Date: Fri, 4 Nov 2022 22:28:43 +0000
Subject: [PATCH] InputManager: Expose pilferPointers API

We can only migrate existing gesture monitors to spy windows if we allow
pilfering from these spy windows. Expose the pilferPointers API so that
other processes can pilfer from arbitrary input windows.

The pilferPointers API is guarded with the MONITOR_INPUT signature
permission.

Bug: 257977069
Test: Build
Change-Id: Ice43ed420502ce3b5e5d37d9ac9e810a51ed07bc
---
 .../android/hardware/input/IInputManager.aidl |  5 ++++
 .../android/hardware/input/InputManager.java  | 28 +++++++++++++++++++
 .../server/input/InputManagerService.java     |  7 +++++
 3 files changed, 40 insertions(+)

diff --git a/core/java/android/hardware/input/IInputManager.aidl b/core/java/android/hardware/input/IInputManager.aidl
index 49c0f9261c53d..fd3d1ac09e3fe 100644
--- a/core/java/android/hardware/input/IInputManager.aidl
+++ b/core/java/android/hardware/input/IInputManager.aidl
@@ -168,4 +168,9 @@ interface IInputManager {
     @JavaPassthrough(annotation="@android.annotation.RequiresPermission(value = "
             + "android.Manifest.permission.BLUETOOTH)")
     String getInputDeviceBluetoothAddress(int deviceId);
+
+    @EnforcePermission("MONITOR_INPUT")
+    @JavaPassthrough(annotation="@android.annotation.RequiresPermission(value = "
+            + "android.Manifest.permission.MONITOR_INPUT)")
+    void pilferPointers(IBinder inputChannelToken);
 }
diff --git a/core/java/android/hardware/input/InputManager.java b/core/java/android/hardware/input/InputManager.java
index 0cf15f76103e0..702b39b8cdaa5 100644
--- a/core/java/android/hardware/input/InputManager.java
+++ b/core/java/android/hardware/input/InputManager.java
@@ -1719,6 +1719,34 @@ public final class InputManager {
         }
     }
 
+    /**
+     * Pilfer pointers from an input channel.
+     *
+     * Takes all the current pointer event streams that are currently being sent to the given
+     * input channel and generates appropriate cancellations for all other windows that are
+     * receiving these pointers.
+     *
+     * This API is intended to be used in conjunction with spy windows. When a spy window pilfers
+     * pointers, the foreground windows and all other spy windows that are receiving any of the
+     * pointers that are currently being dispatched to the pilfering window will have those pointers
+     * canceled. Only the pilfering window will continue to receive events for the affected pointers
+     * until the pointer is lifted.
+     *
+     * This method should be used with caution as unexpected pilfering can break fundamental user
+     * interactions.
+     *
+     * @see android.os.InputConfig#SPY
+     * @hide
+     */
+    @RequiresPermission(Manifest.permission.MONITOR_INPUT)
+    public void pilferPointers(IBinder inputChannelToken) {
+        try {
+            mIm.pilferPointers(inputChannelToken);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
     /**
      * Adds a battery listener to be notified about {@link BatteryState} changes for an input
      * device. The same listener can be registered for multiple input devices.
diff --git a/services/core/java/com/android/server/input/InputManagerService.java b/services/core/java/com/android/server/input/InputManagerService.java
index 31f63d864f6cd..2e735077d74fa 100644
--- a/services/core/java/com/android/server/input/InputManagerService.java
+++ b/services/core/java/com/android/server/input/InputManagerService.java
@@ -2679,6 +2679,13 @@ public class InputManagerService extends IInputManager.Stub
         return mNative.getBluetoothAddress(deviceId);
     }
 
+    @EnforcePermission(Manifest.permission.MONITOR_INPUT)
+    @Override
+    public void pilferPointers(IBinder inputChannelToken) {
+        Objects.requireNonNull(inputChannelToken);
+        mNative.pilferPointers(inputChannelToken);
+    }
+
     @Override
     public void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
         if (!DumpUtils.checkDumpPermission(mContext, TAG, pw)) return;