Merge "Update storage permission policy to use AppCompat APIs." (9af8e0f2) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/policy/SoftRestrictedPermissionPolicy.java

+105 −49

Original line number	Diff line number	Diff line
		@@ -27,16 +27,22 @@ import static android.content.pm.PackageManager.FLAG_PERMISSION_RESTRICTION_SYST
		import static android.content.pm.PackageManager.FLAG_PERMISSION_RESTRICTION_UPGRADE_EXEMPT;
		import static android.content.pm.PackageManager.PERMISSION_GRANTED;

		import static java.lang.Integer.min;

		import android.annotation.NonNull;
		import android.annotation.Nullable;
		import android.app.AppOpsManager;
		import android.compat.annotation.ChangeId;
		import android.compat.annotation.EnabledAfter;
		import android.content.Context;
		import android.content.pm.ApplicationInfo;
		import android.content.pm.PackageManager;
		import android.os.Build;
		import android.os.Binder;
		import android.os.IBinder;
		import android.os.RemoteException;
		import android.os.ServiceManager;
		import android.os.UserHandle;
		import android.util.Log;

		import com.android.internal.compat.IPlatformCompat;

		/**
		* The behavior of soft restricted permissions is different for each permission. This class collects
		@@ -46,6 +52,27 @@ import android.os.UserHandle;
		* {@link com.android.packageinstaller.permission.utils.SoftRestrictedPermissionPolicy}
		*/
		public abstract class SoftRestrictedPermissionPolicy {
		/**
		* Enables scoped storage, with exceptions for apps that explicitly request legacy access, or
		* apps that hold the {@code android.Manifest.permission#WRITE_MEDIA_STORAGE} permission.
		* See https://developer.android.com/training/data-storage#scoped-storage for more information.
		*/
		@ChangeId
		// This change is enabled for apps with targetSDK > {@link android.os.Build.VERSION_CODES.P}
		@EnabledAfter(targetSdkVersion = android.os.Build.VERSION_CODES.P)
		static final long ENABLE_SCOPED_STORAGE = 144914977L;

		/**
		* Enforces scoped storage for all apps, preventing individual apps from opting out. This change
		* has precedence over {@code ENABLE_SCOPED_STORAGE}.
		*/
		@ChangeId
		// This change is enabled for apps with targetSDK > {@link android.os.Build.VERSION_CODES.Q}.
		@EnabledAfter(targetSdkVersion = android.os.Build.VERSION_CODES.Q)
		static final long REQUIRE_SCOPED_STORAGE = 131432978L;

		private static final String LOG_TAG = SoftRestrictedPermissionPolicy.class.getSimpleName();

		private static final int FLAGS_PERMISSION_RESTRICTION_ANY_EXEMPT =
		FLAG_PERMISSION_RESTRICTION_SYSTEM_EXEMPT
		\| FLAG_PERMISSION_RESTRICTION_UPGRADE_EXEMPT
		@@ -59,41 +86,6 @@ public abstract class SoftRestrictedPermissionPolicy {
		}
		};

		/**
		* TargetSDK is per package. To make sure two apps int the same shared UID do not fight over
		* what to set, always compute the combined targetSDK.
		*
		* @param context A context
		* @param appInfo The app that is changed
		* @param user The user the app belongs to
		*
		* @return The minimum targetSDK of all apps sharing the uid of the app
		*/
		private static int getMinimumTargetSDK(@NonNull Context context,
		@NonNull ApplicationInfo appInfo, @NonNull UserHandle user) {
		PackageManager pm = context.getPackageManager();

		int minimumTargetSDK = appInfo.targetSdkVersion;

		String[] uidPkgs = pm.getPackagesForUid(appInfo.uid);
		if (uidPkgs != null) {
		for (String uidPkg : uidPkgs) {
		if (!uidPkg.equals(appInfo.packageName)) {
		ApplicationInfo uidPkgInfo;
		try {
		uidPkgInfo = pm.getApplicationInfoAsUser(uidPkg, 0, user);
		} catch (PackageManager.NameNotFoundException e) {
		continue;
		}

		minimumTargetSDK = min(minimumTargetSDK, uidPkgInfo.targetSdkVersion);
		}
		}
		}

		return minimumTargetSDK;
		}

		/**
		* Get the policy for a soft restricted permission.
		*
		@@ -114,27 +106,31 @@ public abstract class SoftRestrictedPermissionPolicy {
		case READ_EXTERNAL_STORAGE: {
		final boolean isWhiteListed;
		boolean shouldApplyRestriction;
		final int targetSDK;
		final boolean hasRequestedLegacyExternalStorage;
		final boolean hasWriteMediaStorageGrantedForUid;
		final boolean isScopedStorageEnabled;

		if (appInfo != null) {
		PackageManager pm = context.getPackageManager();
		int flags = pm.getPermissionFlags(permission, appInfo.packageName, user);
		isWhiteListed = (flags & FLAGS_PERMISSION_RESTRICTION_ANY_EXEMPT) != 0;
		targetSDK = getMinimumTargetSDK(context, appInfo, user);
		shouldApplyRestriction = (flags & FLAG_PERMISSION_APPLY_RESTRICTION) != 0
		\|\| targetSDK > Build.VERSION_CODES.Q;
		hasRequestedLegacyExternalStorage = hasUidRequestedLegacyExternalStorage(
		appInfo.uid, context);
		hasWriteMediaStorageGrantedForUid = hasWriteMediaStorageGrantedForUid(
		appInfo.uid, context);
		final boolean isScopedStorageRequired =
		isChangeEnabledForUid(context, appInfo, user, REQUIRE_SCOPED_STORAGE);
		isScopedStorageEnabled =
		isChangeEnabledForUid(context, appInfo, user, ENABLE_SCOPED_STORAGE)
		\|\| isScopedStorageRequired;
		shouldApplyRestriction = (flags & FLAG_PERMISSION_APPLY_RESTRICTION) != 0
		\|\| isScopedStorageRequired;
		} else {
		isWhiteListed = false;
		shouldApplyRestriction = false;
		targetSDK = 0;
		hasRequestedLegacyExternalStorage = false;
		hasWriteMediaStorageGrantedForUid = false;
		isScopedStorageEnabled = false;
		}

		// We have a check in PermissionPolicyService.PermissionToOpSynchroniser.setUidMode
		@@ -144,7 +140,7 @@ public abstract class SoftRestrictedPermissionPolicy {
		return new SoftRestrictedPermissionPolicy() {
		@Override
		public boolean mayGrantPermission() {
		return isWhiteListed \|\| targetSDK >= Build.VERSION_CODES.Q;
		return isWhiteListed \|\| isScopedStorageEnabled;
		}
		@Override
		public int getExtraAppOpCode() {
		@@ -152,7 +148,7 @@ public abstract class SoftRestrictedPermissionPolicy {
		}
		@Override
		public boolean mayAllowExtraAppOp() {
		return !shouldApplyRestriction && targetSDK <= Build.VERSION_CODES.Q
		return !shouldApplyRestriction
		&& (hasRequestedLegacyExternalStorage
		\|\| hasWriteMediaStorageGrantedForUid);
		}
		@@ -164,22 +160,26 @@ public abstract class SoftRestrictedPermissionPolicy {
		}
		case WRITE_EXTERNAL_STORAGE: {
		final boolean isWhiteListed;
		final int targetSDK;
		final boolean isScopedStorageEnabled;

		if (appInfo != null) {
		final int flags = context.getPackageManager().getPermissionFlags(permission,
		appInfo.packageName, user);
		isWhiteListed = (flags & FLAGS_PERMISSION_RESTRICTION_ANY_EXEMPT) != 0;
		targetSDK = getMinimumTargetSDK(context, appInfo, user);
		final boolean isScopedStorageRequired =
		isChangeEnabledForUid(context, appInfo, user, REQUIRE_SCOPED_STORAGE);
		isScopedStorageEnabled =
		isChangeEnabledForUid(context, appInfo, user, ENABLE_SCOPED_STORAGE)
		\|\| isScopedStorageRequired;
		} else {
		isWhiteListed = false;
		targetSDK = 0;
		isScopedStorageEnabled = false;
		}

		return new SoftRestrictedPermissionPolicy() {
		@Override
		public boolean mayGrantPermission() {
		return isWhiteListed \|\| targetSDK >= Build.VERSION_CODES.Q;
		return isWhiteListed \|\| isScopedStorageEnabled;
		}
		};
		}
		@@ -188,6 +188,62 @@ public abstract class SoftRestrictedPermissionPolicy {
		}
		}

		/**
		* Checks whether an AppCompat change is enabled for all packages sharing a UID with the
		* provided application.
		*
		* @param context A context to use.
		* @param appInfo The application for which to check whether the compat change is enabled.
		* @param user The user the app belongs to.
		* @param changeId A {@link android.compat.annotation.ChangeId} corresponding to the change.
		*
		* @return true if this change is enabled for all apps sharing the UID of the provided app,
		* false otherwise.
		*/
		private static boolean isChangeEnabledForUid(@NonNull Context context,
		@NonNull ApplicationInfo appInfo, @NonNull UserHandle user, long changeId) {
		PackageManager pm = context.getPackageManager();

		String[] uidPackages = pm.getPackagesForUid(appInfo.uid);
		if (uidPackages != null) {
		for (String uidPackage : uidPackages) {
		ApplicationInfo uidPackageInfo;
		try {
		uidPackageInfo = pm.getApplicationInfoAsUser(uidPackage, 0, user);
		} catch (PackageManager.NameNotFoundException e) {
		continue;
		}
		if (!isChangeEnabled(uidPackageInfo, changeId)) {
		// At least one package sharing this UID does not have this change enabled.
		return false;
		}
		}
		// All packages sharing this UID returned true for {@link #isChangeEnabled()}.
		return true;
		} else {
		Log.w(LOG_TAG, "Check for change " + changeId + " for uid " + appInfo.uid
		+ " produced no packages. Defaulting to using the information for "
		+ appInfo.packageName + " only.");
		return isChangeEnabled(appInfo, changeId);
		}
		}

		private static boolean isChangeEnabled(@NonNull ApplicationInfo appInfo, long changeId) {
		IBinder binder = ServiceManager.getService(Context.PLATFORM_COMPAT_SERVICE);
		IPlatformCompat platformCompat = IPlatformCompat.Stub.asInterface(binder);

		final long callingId = Binder.clearCallingIdentity();

		try {
		return platformCompat.isChangeEnabled(changeId, appInfo);
		} catch (RemoteException e) {
		Log.e(LOG_TAG, "Check for change " + changeId + " failed. Defaulting to enabled.", e);
		return true;
		} finally {
		Binder.restoreCallingIdentity(callingId);
		}
		}

		private static boolean hasUidRequestedLegacyExternalStorage(int uid, @NonNull Context context) {
		PackageManager packageManager = context.getPackageManager();
		String[] packageNames = packageManager.getPackagesForUid(uid);