From 131444d50077884daf4e00c097f1f2335c465c04 Mon Sep 17 00:00:00 2001 From: Robert Carr Date: Sat, 22 Jan 2022 17:28:19 -0800 Subject: [PATCH] SurfaceControlViewHost: Restrict disclosure of input token Currently we send the input (channel) token from the embedded view hierarchy to the remote embedding process via SurfacePackage. This is used to call grantEmbeddedWindowFocus. However this could also allow the host process to invoke updateInputChannel, which is not desirable. To fix this we rework updateInputChannel to work in terms of a focusGrantToken, which only carries this 1 capability. SurfacePackage is modified to not include the input token, but rather include this focus grant token. Bug: 215912712 Test: Existing tests pass Change-Id: Ia9153c54e3e36e73c2b56763b96afab9e9f20d40 --- core/java/android/view/IWindowSession.aidl | 2 +- .../android/view/SurfaceControlViewHost.java | 2 +- .../android/view/WindowlessWindowManager.java | 12 +++++-- .../server/wm/EmbeddedWindowController.java | 35 ++++++++++++++++--- .../java/com/android/server/wm/Session.java | 4 +-- .../server/wm/WindowManagerService.java | 14 +++++--- 6 files changed, 54 insertions(+), 15 deletions(-) diff --git a/core/java/android/view/IWindowSession.aidl b/core/java/android/view/IWindowSession.aidl index 921ce53b3bda9..16154c9fac9cd 100644 --- a/core/java/android/view/IWindowSession.aidl +++ b/core/java/android/view/IWindowSession.aidl @@ -295,7 +295,7 @@ interface IWindowSession { */ void grantInputChannel(int displayId, in SurfaceControl surface, in IWindow window, in IBinder hostInputToken, int flags, int privateFlags, int type, - out InputChannel outInputChannel); + in IBinder focusGrantToken, out InputChannel outInputChannel); /** * Update the flags on an input channel associated with a particular surface. diff --git a/core/java/android/view/SurfaceControlViewHost.java b/core/java/android/view/SurfaceControlViewHost.java index 85a9dbd736edf..22baa692428a8 100644 --- a/core/java/android/view/SurfaceControlViewHost.java +++ b/core/java/android/view/SurfaceControlViewHost.java @@ -274,7 +274,7 @@ public class SurfaceControlViewHost { public @Nullable SurfacePackage getSurfacePackage() { if (mSurfaceControl != null && mAccessibilityEmbeddedConnection != null) { return new SurfacePackage(mSurfaceControl, mAccessibilityEmbeddedConnection, - mViewRoot.getInputToken(), mRemoteInterface); + mWm.getFocusGrantToken(), mRemoteInterface); } else { return null; } diff --git a/core/java/android/view/WindowlessWindowManager.java b/core/java/android/view/WindowlessWindowManager.java index 5176f9bb0f939..2227597c0a238 100644 --- a/core/java/android/view/WindowlessWindowManager.java +++ b/core/java/android/view/WindowlessWindowManager.java @@ -22,6 +22,7 @@ import android.graphics.PixelFormat; import android.graphics.Point; import android.graphics.Rect; import android.graphics.Region; +import android.os.Binder; import android.os.IBinder; import android.os.RemoteCallback; import android.os.RemoteException; @@ -75,6 +76,7 @@ public class WindowlessWindowManager implements IWindowSession { private final Configuration mConfiguration; private final IWindowSession mRealWm; private final IBinder mHostInputToken; + private final IBinder mFocusGrantToken = new Binder(); private int mForceHeight = -1; private int mForceWidth = -1; @@ -91,6 +93,10 @@ public class WindowlessWindowManager implements IWindowSession { mConfiguration.setTo(configuration); } + IBinder getFocusGrantToken() { + return mFocusGrantToken; + } + /** * Utility API. */ @@ -153,10 +159,10 @@ public class WindowlessWindowManager implements IWindowSession { mRealWm.grantInputChannel(displayId, new SurfaceControl(sc, "WindowlessWindowManager.addToDisplay"), window, mHostInputToken, attrs.flags, attrs.privateFlags, attrs.type, - outInputChannel); + mFocusGrantToken, outInputChannel); } else { mRealWm.grantInputChannel(displayId, sc, window, mHostInputToken, attrs.flags, - attrs.privateFlags, attrs.type, outInputChannel); + attrs.privateFlags, attrs.type, mFocusGrantToken, outInputChannel); } } catch (RemoteException e) { Log.e(TAG, "Failed to grant input to surface: ", e); @@ -460,7 +466,7 @@ public class WindowlessWindowManager implements IWindowSession { @Override public void grantInputChannel(int displayId, SurfaceControl surface, IWindow window, - IBinder hostInputToken, int flags, int privateFlags, int type, + IBinder hostInputToken, int flags, int privateFlags, int type, IBinder focusGrantToken, InputChannel outInputChannel) { } diff --git a/services/core/java/com/android/server/wm/EmbeddedWindowController.java b/services/core/java/com/android/server/wm/EmbeddedWindowController.java index 0e2d847796024..e04e3a387b6d2 100644 --- a/services/core/java/com/android/server/wm/EmbeddedWindowController.java +++ b/services/core/java/com/android/server/wm/EmbeddedWindowController.java @@ -41,6 +41,8 @@ class EmbeddedWindowController { private static final String TAG = TAG_WITH_CLASS_NAME ? "EmbeddedWindowController" : TAG_WM; /* maps input token to an embedded window */ private ArrayMap mWindows = new ArrayMap<>(); + private ArrayMap mWindowsByFocusToken = + new ArrayMap<>(); private final Object mGlobalLock; private final ActivityTaskManagerService mAtmService; @@ -59,10 +61,13 @@ class EmbeddedWindowController { void add(IBinder inputToken, EmbeddedWindow window) { try { mWindows.put(inputToken, window); + final IBinder focusToken = window.getFocusGrantToken(); + mWindowsByFocusToken.put(focusToken, window); updateProcessController(window); window.mClient.asBinder().linkToDeath(()-> { synchronized (mGlobalLock) { mWindows.remove(inputToken); + mWindowsByFocusToken.remove(focusToken); } }, 0); } catch (RemoteException e) { @@ -107,8 +112,10 @@ class EmbeddedWindowController { void remove(IWindow client) { for (int i = mWindows.size() - 1; i >= 0; i--) { - if (mWindows.valueAt(i).mClient.asBinder() == client.asBinder()) { + EmbeddedWindow ew = mWindows.valueAt(i); + if (ew.mClient.asBinder() == client.asBinder()) { mWindows.removeAt(i).onRemoved(); + mWindowsByFocusToken.remove(ew.getFocusGrantToken()); return; } } @@ -116,8 +123,10 @@ class EmbeddedWindowController { void onWindowRemoved(WindowState host) { for (int i = mWindows.size() - 1; i >= 0; i--) { - if (mWindows.valueAt(i).mHostWindowState == host) { + EmbeddedWindow ew = mWindows.valueAt(i); + if (ew.mHostWindowState == host) { mWindows.removeAt(i).onRemoved(); + mWindowsByFocusToken.remove(ew.getFocusGrantToken()); } } } @@ -126,6 +135,10 @@ class EmbeddedWindowController { return mWindows.get(inputToken); } + EmbeddedWindow getByFocusToken(IBinder focusGrantToken) { + return mWindowsByFocusToken.get(focusGrantToken); + } + void onActivityRemoved(ActivityRecord activityRecord) { for (int i = mWindows.size() - 1; i >= 0; i--) { final EmbeddedWindow window = mWindows.valueAt(i); @@ -157,6 +170,8 @@ class EmbeddedWindowController { // and this variable is mostly used for tracking that. boolean mIsOverlay = false; + private IBinder mFocusGrantToken; + /** * @param session calling session to check ownership of the window * @param clientToken client token used to clean up the map if the embedding process dies @@ -171,7 +186,7 @@ class EmbeddedWindowController { */ EmbeddedWindow(Session session, WindowManagerService service, IWindow clientToken, WindowState hostWindowState, int ownerUid, int ownerPid, int windowType, - int displayId) { + int displayId, IBinder focusGrantToken) { mSession = session; mWmService = service; mClient = clientToken; @@ -182,6 +197,7 @@ class EmbeddedWindowController { mOwnerPid = ownerPid; mWindowType = windowType; mDisplayId = displayId; + mFocusGrantToken = focusGrantToken; } @Override @@ -242,6 +258,17 @@ class EmbeddedWindowController { return mIsOverlay; } + IBinder getFocusGrantToken() { + return mFocusGrantToken; + } + + IBinder getInputChannelToken() { + if (mInputChannel != null) { + return mInputChannel.getToken(); + } + return null; + } + /** * System hosted overlays need the WM to invoke grantEmbeddedWindowFocus and * so we need to participate inside handlePointerDownOutsideFocus logic @@ -255,7 +282,7 @@ class EmbeddedWindowController { private void handleTap(boolean grantFocus) { if (mInputChannel != null) { - mWmService.grantEmbeddedWindowFocus(mSession, mInputChannel.getToken(), grantFocus); + mWmService.grantEmbeddedWindowFocus(mSession, mFocusGrantToken, grantFocus); } } diff --git a/services/core/java/com/android/server/wm/Session.java b/services/core/java/com/android/server/wm/Session.java index 005544b961c32..3dd5532f8f6b2 100644 --- a/services/core/java/com/android/server/wm/Session.java +++ b/services/core/java/com/android/server/wm/Session.java @@ -798,7 +798,7 @@ class Session extends IWindowSession.Stub implements IBinder.DeathRecipient { @Override public void grantInputChannel(int displayId, SurfaceControl surface, IWindow window, IBinder hostInputToken, int flags, int privateFlags, int type, - InputChannel outInputChannel) { + IBinder focusGrantToken, InputChannel outInputChannel) { if (hostInputToken == null && !mCanAddInternalSystemWindow) { // Callers without INTERNAL_SYSTEM_WINDOW permission cannot grant input channel to // embedded windows without providing a host window input token @@ -814,7 +814,7 @@ class Session extends IWindowSession.Stub implements IBinder.DeathRecipient { try { mService.grantInputChannel(this, mUid, mPid, displayId, surface, window, hostInputToken, flags, mCanAddInternalSystemWindow ? privateFlags : 0, - mCanAddInternalSystemWindow ? type : 0, outInputChannel); + mCanAddInternalSystemWindow ? type : 0, focusGrantToken, outInputChannel); } finally { Binder.restoreCallingIdentity(identity); } diff --git a/services/core/java/com/android/server/wm/WindowManagerService.java b/services/core/java/com/android/server/wm/WindowManagerService.java index 2f0ef4a8ee1b4..e3cbb66c1b05c 100644 --- a/services/core/java/com/android/server/wm/WindowManagerService.java +++ b/services/core/java/com/android/server/wm/WindowManagerService.java @@ -8263,7 +8263,8 @@ public class WindowManagerService extends IWindowManager.Stub */ void grantInputChannel(Session session, int callingUid, int callingPid, int displayId, SurfaceControl surface, IWindow window, IBinder hostInputToken, - int flags, int privateFlags, int type, InputChannel outInputChannel) { + int flags, int privateFlags, int type, IBinder focusGrantToken, + InputChannel outInputChannel) { final InputApplicationHandle applicationHandle; final String name; final InputChannel clientChannel; @@ -8271,7 +8272,7 @@ public class WindowManagerService extends IWindowManager.Stub EmbeddedWindowController.EmbeddedWindow win = new EmbeddedWindowController.EmbeddedWindow(session, this, window, mInputToWindowMap.get(hostInputToken), callingUid, callingPid, type, - displayId); + displayId, focusGrantToken); clientChannel = win.openInputChannel(); mEmbeddedWindowController.add(clientChannel.getToken(), win); applicationHandle = win.getApplicationHandle(); @@ -8538,10 +8539,10 @@ public class WindowManagerService extends IWindowManager.Stub } } - void grantEmbeddedWindowFocus(Session session, IBinder inputToken, boolean grantFocus) { + void grantEmbeddedWindowFocus(Session session, IBinder focusToken, boolean grantFocus) { synchronized (mGlobalLock) { final EmbeddedWindowController.EmbeddedWindow embeddedWindow = - mEmbeddedWindowController.get(inputToken); + mEmbeddedWindowController.getByFocusToken(focusToken); if (embeddedWindow == null) { Slog.e(TAG, "Embedded window not found"); return; @@ -8550,6 +8551,11 @@ public class WindowManagerService extends IWindowManager.Stub Slog.e(TAG, "Window not in session:" + session); return; } + IBinder inputToken = embeddedWindow.getInputChannelToken(); + if (inputToken == null) { + Slog.e(TAG, "Focus token found but input channel token not found"); + return; + } SurfaceControl.Transaction t = mTransactionFactory.get(); final int displayId = embeddedWindow.mDisplayId; if (grantFocus) {