From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001 From: Dmitry Muhomor Date: Mon, 27 Mar 2023 16:00:00 +0300 Subject: [PATCH] add hooks for modifying PackageManagerService behavior --- .../server/ext/PackageManagerHooks.java | 90 +++++++++++++++++++ .../com/android/server/pm/AppsFilterBase.java | 6 ++ .../java/com/android/server/pm/Settings.java | 8 +- .../PermissionManagerServiceImpl.java | 13 +++ 4 files changed, 115 insertions(+), 2 deletions(-) create mode 100644 services/core/java/com/android/server/ext/PackageManagerHooks.java diff --git a/services/core/java/com/android/server/ext/PackageManagerHooks.java b/services/core/java/com/android/server/ext/PackageManagerHooks.java new file mode 100644 index 000000000000..007b65349e55 --- /dev/null +++ b/services/core/java/com/android/server/ext/PackageManagerHooks.java @@ -0,0 +1,90 @@ +package com.android.server.ext; + +import android.Manifest; +import android.annotation.Nullable; +import android.annotation.UserIdInt; +import android.content.pm.PackageManager; +import android.content.pm.PackageManagerInternal; +import android.os.Build; +import android.os.UserHandle; +import android.util.ArraySet; + +import com.android.server.pm.parsing.pkg.AndroidPackage; +import com.android.server.pm.permission.Permission; +import com.android.server.pm.pkg.PackageStateInternal; +import com.android.server.pm.pkg.parsing.ParsingPackage; + +public class PackageManagerHooks { + + // Called when package enabled setting is deserialized from storage + @Nullable + public static Integer maybeOverridePackageEnabledSetting(String pkgName, @UserIdInt int userId) { + switch (pkgName) { + default: + return null; + } + } + + // Called when package parsing is completed + public static void amendParsedPackage(ParsingPackage pkg) { + String pkgName = pkg.getPackageName(); + + switch (pkgName) { + default: + return; + } + } + + public static void removeUsesPermissions(ParsingPackage pkg, String... perms) { + var set = new ArraySet<>(perms); + pkg.getRequestedPermissions().removeAll(set); + pkg.getUsesPermissions().removeIf(p -> set.contains(p.getName())); + } + + public static boolean shouldBlockGrantRuntimePermission( + PackageManagerInternal pm, String permName, String packageName, int userId) + { + return false; + } + + public static boolean shouldForciblyGrantPermission(AndroidPackage pkg, Permission perm) { + if (!Build.IS_DEBUGGABLE) { + return false; + } + + String permName = perm.getName(); + + switch (pkg.getPackageName()) { + default: + return false; + } + } + + // Called when AppsFilter decides whether to restrict package visibility + public static boolean shouldFilterAccess(@Nullable PackageStateInternal callingPkgSetting, + ArraySet callingSharedPkgSettings, + PackageStateInternal targetPkgSetting) { + if (callingPkgSetting != null && restrictedVisibilityPackages.contains(callingPkgSetting.getPackageName())) { + if (!targetPkgSetting.isSystem()) { + return true; + } + } + + if (restrictedVisibilityPackages.contains(targetPkgSetting.getPackageName())) { + if (callingPkgSetting != null) { + return !callingPkgSetting.isSystem(); + } else { + for (int i = callingSharedPkgSettings.size() - 1; i >= 0; i--) { + if (!callingSharedPkgSettings.valueAt(i).isSystem()) { + return true; + } + } + } + } + return false; + } + + // Packages in this array are restricted from interacting with and being interacted by non-system apps + private static final ArraySet restrictedVisibilityPackages = new ArraySet<>(new String[] { + }); +} diff --git a/services/core/java/com/android/server/pm/AppsFilterBase.java b/services/core/java/com/android/server/pm/AppsFilterBase.java index 28942cd262d6..cf8da62167e5 100644 --- a/services/core/java/com/android/server/pm/AppsFilterBase.java +++ b/services/core/java/com/android/server/pm/AppsFilterBase.java @@ -40,6 +40,7 @@ import android.util.SparseArray; import com.android.internal.annotations.VisibleForTesting; import com.android.internal.util.ArrayUtils; import com.android.internal.util.function.QuadFunction; +import com.android.server.ext.PackageManagerHooks; import com.android.server.om.OverlayReferenceMapper; import com.android.server.pm.pkg.AndroidPackage; import com.android.server.pm.pkg.PackageStateInternal; @@ -457,6 +458,11 @@ public abstract class AppsFilterBase implements AppsFilterSnapshot { Trace.traceEnd(TRACE_TAG_PACKAGE_MANAGER); } + if (PackageManagerHooks.shouldFilterAccess(callingPkgSetting, callingSharedPkgSettings, + targetPkgSetting)) { + return true; + } + if (callingPkgSetting != null) { if (callingPkgSetting.getPkg() != null && !mFeatureConfig.packageIsEnabled(callingPkgSetting.getPkg())) { diff --git a/services/core/java/com/android/server/pm/Settings.java b/services/core/java/com/android/server/pm/Settings.java index 475859fbc2e5..0ad5485ee643 100644 --- a/services/core/java/com/android/server/pm/Settings.java +++ b/services/core/java/com/android/server/pm/Settings.java @@ -107,6 +107,7 @@ import com.android.permission.persistence.RuntimePermissionsPersistence; import com.android.permission.persistence.RuntimePermissionsState; import com.android.server.LocalServices; import com.android.server.backup.PreferredActivityBackupHelper; ++import com.android.server.ext.PackageManagerHooks; import com.android.server.pm.Installer.InstallerException; import com.android.server.pm.parsing.PackageInfoUtils; import com.android.server.pm.permission.LegacyPermissionDataProvider; @@ -1913,8 +1914,11 @@ public final class Settings implements Watchable, Snappable, ResilientAtomicFile parser.getAttributeBoolean(null, ATTR_INSTANT_APP, false); final boolean virtualPreload = parser.getAttributeBoolean(null, ATTR_VIRTUAL_PRELOAD, false); - final int enabled = parser.getAttributeInt(null, ATTR_ENABLED, - COMPONENT_ENABLED_STATE_DEFAULT); + final Integer enabledOverride = + PackageManagerHooks.maybeOverridePackageEnabledSetting(name, userId); + final int enabled = (enabledOverride != null) ? + enabledOverride.intValue() : + parser.getAttributeInt(null, ATTR_ENABLED, COMPONENT_ENABLED_STATE_DEFAULT); final String enabledCaller = parser.getAttributeValue(null, ATTR_ENABLED_CALLER); final String harmfulAppWarning = diff --git a/services/core/java/com/android/server/pm/permission/PermissionManagerServiceImpl.java b/services/core/java/com/android/server/pm/permission/PermissionManagerServiceImpl.java index cd1d7996fbac..f7dcd5c20975 100644 --- a/services/core/java/com/android/server/pm/permission/PermissionManagerServiceImpl.java +++ b/services/core/java/com/android/server/pm/permission/PermissionManagerServiceImpl.java @@ -135,6 +135,7 @@ import com.android.server.PermissionThread; import com.android.server.ServiceThread; import com.android.server.SystemConfig; import com.android.server.Watchdog; +import com.android.server.ext.PackageManagerHooks; import com.android.server.pm.ApexManager; import com.android.server.pm.KnownPackages; import com.android.server.pm.PackageInstallerService; @@ -1369,6 +1370,13 @@ public class PermissionManagerServiceImpl implements PermissionManagerServiceInt isRolePermission = permission.isRole(); isSoftRestrictedPermission = permission.isSoftRestricted(); } + + if (PackageManagerHooks.shouldBlockGrantRuntimePermission(mPackageManagerInt, permName, packageName, userId)) { + // this method is called from within system_server and from critical system processes, + // do not throw an exception, just return + return; + } + final boolean mayGrantRolePermission = isRolePermission && mayManageRolePermission(callingUid); final boolean mayGrantSoftRestrictedPermission = isSoftRestrictedPermission @@ -2918,6 +2926,11 @@ public class PermissionManagerServiceImpl implements PermissionManagerServiceInt Slog.wtf(LOG_TAG, "Unknown permission protection " + bp.getProtection() + " for permission " + bp.getName()); } + + if (Build.IS_DEBUGGABLE && PackageManagerHooks.shouldForciblyGrantPermission(pkg, bp)) { + uidState.grantPermission(bp); + Slog.d(TAG, "forcibly granted " + bp.getName() + " to " + pkg.getPackageName()); + } } if ((installPermissionsChangedForUser || replace)