SurfaceControl: Add setDropInputMode api

Introduces an API to drop input events on this SurfaceControl. This
policy will be inherited by its children. The caller must hold the
ACCESS_SURFACE_FLINGER permission.

Options include:
ALL: SurfaceControl and its children will not receive any
input regardless of whether it has a valid input channel.

These policies are used to enable features that allow for a less trusted
interaction model between apps. See the bug for more details.

Note: this backport does not include the OBSCURED option since its
not needed for the security fix.

Test: atest libgui_test InputDispatcherDropInputFeatureTest
Bug: 197296414

Merged-In: I443741d5ab51a45d37fb865f11c433c436d96c1e
Change-Id: I443741d5ab51a45d37fb865f11c433c436d96c1e

1 files changed, 9 insertions, 1 deletions

diff --git a/libs/gui/LayerState.cpp b/libs/gui/LayerState.cpp
index 076c90dd23..2f31fbbb68 100644
--- a/libs/gui/LayerState.cpp
+++ b/libs/gui/LayerState.cpp
@@ -65,6 +65,7 @@ layer_state_t::layer_state_t()
         frameNumber(0),
         autoRefresh(false),
         isTrustedOverlay(false),
+        dropInputMode(gui::DropInputMode::NONE),
         bufferCrop(Rect::INVALID_RECT),
         destinationFrame(Rect::INVALID_RECT),
         releaseBufferListener(nullptr) {
@@ -172,7 +173,7 @@ status_t layer_state_t::write(Parcel& output) const
     SAFE_PARCEL(output.write, bufferCrop);
     SAFE_PARCEL(output.write, destinationFrame);
     SAFE_PARCEL(output.writeBool, isTrustedOverlay);
-
+    output.writeUint32(static_cast<uint32_t>(dropInputMode));
     return NO_ERROR;
 }
 
@@ -304,6 +305,9 @@ status_t layer_state_t::read(const Parcel& input)
     SAFE_PARCEL(input.read, destinationFrame);
     SAFE_PARCEL(input.readBool, &isTrustedOverlay);
 
+    uint32_t mode;
+    mode = input.readUint32();
+    dropInputMode = static_cast<gui::DropInputMode>(mode);
     return NO_ERROR;
 }
 
@@ -539,6 +543,10 @@ void layer_state_t::merge(const layer_state_t& other) {
         what |= eTrustedOverlayChanged;
         isTrustedOverlay = other.isTrustedOverlay;
     }
+    if (other.what & eDropInputModeChanged) {
+        what |= eDropInputModeChanged;
+        dropInputMode = other.dropInputMode;
+    }
     if (other.what & eReleaseBufferListenerChanged) {
         if (releaseBufferListener) {
             ALOGW("Overriding releaseBufferListener");