Let update owners can relinquish update ownership (5/n)

Add a new API to let the update owner can relinquish update ownership.
This API can be only used by the the current update owner.

Bug: 244413073
Test: atest CtsPackageInstallTestCases:UpdateOwnershipEnforcementTest
Change-Id: I8dda2c2502b9dc8db6b23be2b766dc738a9b6742

core/api/current.txt

@@ -12258,6 +12258,7 @@ package android.content.pm {
     method @NonNull public java.util.List<android.content.pm.PackageManager.Property> queryProviderProperty(@NonNull String);
     method @NonNull public java.util.List<android.content.pm.PackageManager.Property> queryReceiverProperty(@NonNull String);
     method @NonNull public java.util.List<android.content.pm.PackageManager.Property> queryServiceProperty(@NonNull String);
+    method public void relinquishUpdateOwnership(@NonNull String);
     method @Deprecated public abstract void removePackageFromPreferred(@NonNull String);
     method public abstract void removePermission(@NonNull String);
     method @RequiresPermission(value="android.permission.WHITELIST_RESTRICTED_PERMISSIONS", conditional=true) public boolean removeWhitelistedRestrictedPermission(@NonNull String, @NonNull String, int);

core/java/android/app/ApplicationPackageManager.java

@@ -3890,4 +3890,14 @@ public class ApplicationPackageManager extends PackageManager {
         return Settings.Global.getInt(mContext.getContentResolver(),
                 Settings.Global.SHOW_NEW_APP_INSTALLED_NOTIFICATION_ENABLED, 0) == 1;
     }
+
+    @Override
+    public void relinquishUpdateOwnership(String targetPackage) {
+        Objects.requireNonNull(targetPackage);
+        try {
+            mPM.relinquishUpdateOwnership(targetPackage);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
 }

core/java/android/content/pm/IPackageManager.aidl

@@ -214,6 +214,8 @@ interface IPackageManager {
     @UnsupportedAppUsage
     void setInstallerPackageName(in String targetPackage, in String installerPackageName);
 
+    void relinquishUpdateOwnership(in String targetPackage);
+
     void setApplicationCategoryHint(String packageName, int categoryHint, String callerPackageName);
 
     /** @deprecated rawr, don't call AIDL methods directly! */

core/java/android/content/pm/PackageManager.java

@@ -10866,4 +10866,16 @@ public abstract class PackageManager {
         throw new UnsupportedOperationException(
                 "isShowNewAppInstalledNotificationEnabled not implemented in subclass");
     }
+
+    /**
+     * Attempt to relinquish the update ownership of the given package. Only the current
+     * update owner of the given package can use this API or a SecurityException will be
+     * thrown.
+     *
+     * @param targetPackage The installed package whose update owner will be changed.
+     */
+    public void relinquishUpdateOwnership(@NonNull String targetPackage) {
+        throw new UnsupportedOperationException(
+                "relinquishUpdateOwnership not implemented in subclass");
+    }
 }

services/core/java/com/android/server/pm/PackageManagerService.java

@@ -6012,6 +6012,42 @@ public class PackageManagerService implements PackageSender, TestUtilityService
             }
         }
 
+        @Override
+        public void relinquishUpdateOwnership(String targetPackage) {
+            final int callingUid = Binder.getCallingUid();
+            final int callingUserId = UserHandle.getUserId(callingUid);
+            final Computer snapshot = snapshotComputer();
+
+            final PackageStateInternal targetPackageState =
+                    snapshot.getPackageStateForInstalledAndFiltered(targetPackage, callingUid,
+                            callingUserId);
+            if (targetPackageState == null) {
+                throw new IllegalArgumentException("Unknown target package: " + targetPackage);
+            }
+
+            final String targetUpdateOwnerPackageName =
+                    targetPackageState.getInstallSource().mUpdateOwnerPackageName;
+            final PackageStateInternal targetUpdateOwnerPkgSetting =
+                    targetUpdateOwnerPackageName == null ? null
+                            : snapshot.getPackageStateInternal(targetUpdateOwnerPackageName);
+
+            if (targetUpdateOwnerPkgSetting == null) {
+                return;
+            }
+
+            final int callingAppId = UserHandle.getAppId(callingUid);
+            final int targetUpdateOwnerAppId = targetUpdateOwnerPkgSetting.getAppId();
+            if (callingAppId != Process.SYSTEM_UID
+                    && callingAppId != Process.SHELL_UID
+                    && callingAppId != targetUpdateOwnerAppId) {
+                throw new SecurityException("Caller is not the current update owner.");
+            }
+
+            commitPackageStateMutation(null /* initialState */, targetPackage,
+                    state -> state.setUpdateOwner(null /* updateOwnerPackageName */));
+            scheduleWriteSettings();
+        }
+
         @Override
         public boolean setInstantAppCookie(String packageName, byte[] cookie, int userId) {
             if (HIDE_EPHEMERAL_APIS) {

services/core/java/com/android/server/pm/pkg/mutate/PackageStateMutator.java

@@ -291,6 +291,15 @@ public class PackageStateMutator {
             return this;
         }
 
+        @NonNull
+        @Override
+        public PackageStateWrite setUpdateOwner(@NonNull String updateOwnerPackageName) {
+            if (mState != null) {
+                mState.setUpdateOwnerPackage(updateOwnerPackageName);
+            }
+            return this;
+        }
+
         private static class UserStateWriteWrapper implements PackageUserStateWrite {
 
             @Nullable

services/core/java/com/android/server/pm/pkg/mutate/PackageStateWrite.java

@@ -57,4 +57,7 @@ public interface PackageStateWrite {
 
     @NonNull
     PackageStateWrite setInstaller(@Nullable String installerPackageName, int installerPackageUid);
+
+    @NonNull
+    PackageStateWrite setUpdateOwner(@Nullable String updateOwnerPackageName);
 }