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authorNate Jiang <qiangjiang@google.com>2020-12-03 14:31:30 -0800
committerRoshan Pius <rpius@google.com>2021-01-05 17:17:32 +0000
commite26f3b9ffe1c862c8c8322a6ae7b03ce8f9900f9 (patch)
tree1c20340d5d0b7b78efed23008ad0f845e3abccbb
parentb82fdddc89d5ce3c36b59bc3e0e4d246ec229a62 (diff)
[Suggestion] Check foreground user for API call
Also, squashes the follow up commit to create a single CL for backporting: ======= PasspointManager: Don't allow bg user to modify passpoint profiles Also, add safety net logging for this bug. ======= Bug: 174749461 Test: atest com.android.server.wifi Change-Id: Ifc79ffeb04a7be99a9c60d9414b72e88275c0514 Merged-In: Ifc79ffeb04a7be99a9c60d9414b72e88275c0514 (cherry picked from commit e799efba85cbe52044a067869af71d9c15b573bb) (cherry picked from commit 23685b8604571ec623e539f4f9c66db65c9dde81)
-rw-r--r--service/java/com/android/server/wifi/WifiConfigManager.java44
-rw-r--r--service/java/com/android/server/wifi/WifiInjector.java2
-rw-r--r--service/java/com/android/server/wifi/WifiStateMachine.java4
-rw-r--r--service/java/com/android/server/wifi/hotspot2/PasspointManager.java17
-rw-r--r--service/java/com/android/server/wifi/util/WifiPermissionsUtil.java29
-rw-r--r--tests/wifitests/src/com/android/server/wifi/WifiConfigManagerTest.java18
-rw-r--r--tests/wifitests/src/com/android/server/wifi/WifiStateMachineTest.java4
-rw-r--r--tests/wifitests/src/com/android/server/wifi/hotspot2/PasspointManagerTest.java12
8 files changed, 82 insertions, 48 deletions
diff --git a/service/java/com/android/server/wifi/WifiConfigManager.java b/service/java/com/android/server/wifi/WifiConfigManager.java
index c06e80239..28ac2056b 100644
--- a/service/java/com/android/server/wifi/WifiConfigManager.java
+++ b/service/java/com/android/server/wifi/WifiConfigManager.java
@@ -743,28 +743,6 @@ public class WifiConfigManager {
}
/**
- * Check if the given UID belongs to the current foreground user. This is
- * used to prevent apps running in background users from modifying network
- * configurations.
- * <p>
- * UIDs belonging to system internals (such as SystemUI) are always allowed,
- * since they always run as {@link UserHandle#USER_SYSTEM}.
- *
- * @param uid uid of the app.
- * @return true if the given UID belongs to the current foreground user,
- * otherwise false.
- */
- private boolean doesUidBelongToCurrentUser(int uid) {
- if (uid == android.os.Process.SYSTEM_UID || uid == mSystemUiUid) {
- return true;
- } else {
- return WifiConfigurationUtil.doesUidBelongToAnyProfile(
- uid, mUserManager.getProfiles(mCurrentUserId));
- }
- }
-
- /**
- * Copy over public elements from an external WifiConfiguration object to the internal
* configuration object if element has been set in the provided external WifiConfiguration.
* The only exception is the hidden |IpConfiguration| parameters, these need to be copied over
* for every update.
@@ -1097,7 +1075,7 @@ public class WifiConfigManager {
* @return NetworkUpdateResult object representing status of the update.
*/
public NetworkUpdateResult addOrUpdateNetwork(WifiConfiguration config, int uid) {
- if (!doesUidBelongToCurrentUser(uid)) {
+ if (!mWifiPermissionsUtil.doesUidBelongToCurrentUser(uid)) {
Log.e(TAG, "UID " + uid + " not visible to the current user");
return new NetworkUpdateResult(WifiConfiguration.INVALID_NETWORK_ID);
}
@@ -1173,7 +1151,7 @@ public class WifiConfigManager {
* @return true if successful, false otherwise.
*/
public boolean removeNetwork(int networkId, int uid) {
- if (!doesUidBelongToCurrentUser(uid)) {
+ if (!mWifiPermissionsUtil.doesUidBelongToCurrentUser(uid)) {
Log.e(TAG, "UID " + uid + " not visible to the current user");
return false;
}
@@ -1510,7 +1488,7 @@ public class WifiConfigManager {
if (mVerboseLoggingEnabled) {
Log.v(TAG, "Enabling network " + networkId + " (disableOthers " + disableOthers + ")");
}
- if (!doesUidBelongToCurrentUser(uid)) {
+ if (!mWifiPermissionsUtil.doesUidBelongToCurrentUser(uid)) {
Log.e(TAG, "UID " + uid + " not visible to the current user");
return false;
}
@@ -1545,7 +1523,7 @@ public class WifiConfigManager {
if (mVerboseLoggingEnabled) {
Log.v(TAG, "Disabling network " + networkId);
}
- if (!doesUidBelongToCurrentUser(uid)) {
+ if (!mWifiPermissionsUtil.doesUidBelongToCurrentUser(uid)) {
Log.e(TAG, "UID " + uid + " not visible to the current user");
return false;
}
@@ -1580,7 +1558,7 @@ public class WifiConfigManager {
if (mVerboseLoggingEnabled) {
Log.v(TAG, "Update network last connect UID for " + networkId);
}
- if (!doesUidBelongToCurrentUser(uid)) {
+ if (!mWifiPermissionsUtil.doesUidBelongToCurrentUser(uid)) {
Log.e(TAG, "UID " + uid + " not visible to the current user");
return false;
}
@@ -2663,8 +2641,8 @@ public class WifiConfigManager {
Set<Integer> removedNetworkIds = new HashSet<>();
// Remove any private networks of the old user before switching the userId.
for (WifiConfiguration config : getInternalConfiguredNetworks()) {
- if (!config.shared && WifiConfigurationUtil.doesUidBelongToAnyProfile(
- config.creatorUid, mUserManager.getProfiles(userId))) {
+ if (!config.shared && !mWifiPermissionsUtil
+ .doesUidBelongToCurrentUser(config.creatorUid)) {
removedNetworkIds.add(config.networkId);
localLog("clearInternalUserData: removed config."
+ " netId=" + config.networkId
@@ -2886,8 +2864,8 @@ public class WifiConfigManager {
// Migrate the legacy Passpoint configurations owned by the current user to
// {@link PasspointManager}.
- if (config.isLegacyPasspointConfig && WifiConfigurationUtil.doesUidBelongToAnyProfile(
- config.creatorUid, mUserManager.getProfiles(mCurrentUserId))) {
+ if (config.isLegacyPasspointConfig && !mWifiPermissionsUtil
+ .doesUidBelongToCurrentUser(config.creatorUid)) {
legacyPasspointNetId.add(config.networkId);
// Migrate the legacy Passpoint configuration and add it to PasspointManager.
if (!PasspointManager.addLegacyPasspointConfig(config)) {
@@ -2904,8 +2882,8 @@ public class WifiConfigManager {
// because all networks were previously stored in a central file. We cannot
// write these private networks to the user specific store until the corresponding
// user logs in.
- if (config.shared || !WifiConfigurationUtil.doesUidBelongToAnyProfile(
- config.creatorUid, mUserManager.getProfiles(mCurrentUserId))) {
+ if (config.shared || !mWifiPermissionsUtil
+ .doesUidBelongToCurrentUser(config.creatorUid)) {
sharedConfigurations.add(config);
} else {
userConfigurations.add(config);
diff --git a/service/java/com/android/server/wifi/WifiInjector.java b/service/java/com/android/server/wifi/WifiInjector.java
index 89a7f45b4..cd07187dc 100644
--- a/service/java/com/android/server/wifi/WifiInjector.java
+++ b/service/java/com/android/server/wifi/WifiInjector.java
@@ -245,7 +245,7 @@ public class WifiInjector {
mSimAccessor = new SIMAccessor(mContext);
mPasspointManager = new PasspointManager(mContext, mWifiNative, mWifiKeyStore, mClock,
mSimAccessor, new PasspointObjectFactory(), mWifiConfigManager, mWifiConfigStore,
- mWifiMetrics);
+ mWifiMetrics, mWifiPermissionsUtil);
mPasspointNetworkEvaluator = new PasspointNetworkEvaluator(
mPasspointManager, mWifiConfigManager, mConnectivityLocalLog);
mWifiMetrics.setPasspointManager(mPasspointManager);
diff --git a/service/java/com/android/server/wifi/WifiStateMachine.java b/service/java/com/android/server/wifi/WifiStateMachine.java
index 390a10238..dff2d6077 100644
--- a/service/java/com/android/server/wifi/WifiStateMachine.java
+++ b/service/java/com/android/server/wifi/WifiStateMachine.java
@@ -3503,7 +3503,7 @@ public class WifiStateMachine extends StateMachine {
break;
case CMD_REMOVE_PASSPOINT_CONFIG:
int removeResult = mPasspointManager.removeProvider(
- (String) message.obj) ? SUCCESS : FAILURE;
+ message.sendingUid, (String) message.obj) ? SUCCESS : FAILURE;
replyToMessage(message, message.what, removeResult);
break;
case CMD_GET_PASSPOINT_CONFIGS:
@@ -4375,7 +4375,7 @@ public class WifiStateMachine extends StateMachine {
break;
case CMD_REMOVE_PASSPOINT_CONFIG:
String fqdn = (String) message.obj;
- if (mPasspointManager.removeProvider(fqdn)) {
+ if (mPasspointManager.removeProvider(message.sendingUid, fqdn)) {
if (isProviderOwnedNetwork(mTargetNetworkId, fqdn)
|| isProviderOwnedNetwork(mLastNetworkId, fqdn)) {
logd("Disconnect from current network since its provider is removed");
diff --git a/service/java/com/android/server/wifi/hotspot2/PasspointManager.java b/service/java/com/android/server/wifi/hotspot2/PasspointManager.java
index 988dd6642..5d3ffe3f7 100644
--- a/service/java/com/android/server/wifi/hotspot2/PasspointManager.java
+++ b/service/java/com/android/server/wifi/hotspot2/PasspointManager.java
@@ -41,6 +41,7 @@ import com.android.server.wifi.hotspot2.anqp.HSOsuProvidersElement;
import com.android.server.wifi.hotspot2.anqp.OsuProviderInfo;
import com.android.server.wifi.util.InformationElementUtil;
import com.android.server.wifi.util.ScanResultUtil;
+import com.android.server.wifi.util.WifiPermissionsUtil;
import java.io.PrintWriter;
import java.util.ArrayList;
@@ -88,6 +89,7 @@ public class PasspointManager {
private final CertificateVerifier mCertVerifier;
private final WifiMetrics mWifiMetrics;
private final PasspointProvisioner mPasspointProvisioner;
+ private final WifiPermissionsUtil mWifiPermissionsUtil;
// Counter used for assigning unique identifier to each provider.
private long mProviderIndex;
@@ -160,7 +162,7 @@ public class PasspointManager {
public PasspointManager(Context context, WifiNative wifiNative, WifiKeyStore keyStore,
Clock clock, SIMAccessor simAccessor, PasspointObjectFactory objectFactory,
WifiConfigManager wifiConfigManager, WifiConfigStore wifiConfigStore,
- WifiMetrics wifiMetrics) {
+ WifiMetrics wifiMetrics, WifiPermissionsUtil wifiPermissionsUtil) {
mHandler = objectFactory.makePasspointEventHandler(wifiNative,
new CallbackHandler(context));
mKeyStore = keyStore;
@@ -177,6 +179,7 @@ public class PasspointManager {
mKeyStore, mSimAccessor, new DataSourceHandler()));
mPasspointProvisioner = objectFactory.makePasspointProvisioner(context);
sPasspointManager = this;
+ mWifiPermissionsUtil = wifiPermissionsUtil;
}
/**
@@ -214,6 +217,10 @@ public class PasspointManager {
Log.e(TAG, "Invalid configuration");
return false;
}
+ if (!mWifiPermissionsUtil.doesUidBelongToCurrentUser(uid)) {
+ Log.e(TAG, "UID " + uid + " not visible to the current user");
+ return false;
+ }
// For Hotspot 2.0 Release 1, the CA Certificate must be trusted by one of the pre-loaded
// public CAs in the system key store on the device. Since the provisioning method
@@ -257,16 +264,20 @@ public class PasspointManager {
/**
* Remove a Passpoint provider identified by the given FQDN.
*
+ * @param callingUid Calling UID.
* @param fqdn The FQDN of the provider to remove
* @return true if a provider is removed, false otherwise
*/
- public boolean removeProvider(String fqdn) {
+ public boolean removeProvider(int callingUid, String fqdn) {
mWifiMetrics.incrementNumPasspointProviderUninstallation();
if (!mProviders.containsKey(fqdn)) {
Log.e(TAG, "Config doesn't exist");
return false;
}
-
+ if (!mWifiPermissionsUtil.doesUidBelongToCurrentUser(callingUid)) {
+ Log.e(TAG, "UID " + callingUid + " not visible to the current user");
+ return false;
+ }
mProviders.get(fqdn).uninstallCertsAndKeys();
mProviders.remove(fqdn);
mWifiConfigManager.saveToStore(true /* forceWrite */);
diff --git a/service/java/com/android/server/wifi/util/WifiPermissionsUtil.java b/service/java/com/android/server/wifi/util/WifiPermissionsUtil.java
index 1a85c28ae..175b2a695 100644
--- a/service/java/com/android/server/wifi/util/WifiPermissionsUtil.java
+++ b/service/java/com/android/server/wifi/util/WifiPermissionsUtil.java
@@ -24,6 +24,7 @@ import android.content.pm.UserInfo;
import android.os.RemoteException;
import android.os.UserManager;
import android.provider.Settings;
+import android.util.EventLog;
import com.android.server.wifi.WifiInjector;
import com.android.server.wifi.WifiLog;
@@ -296,4 +297,32 @@ public class WifiPermissionsUtil {
android.Manifest.permission.NETWORK_SETUP_WIZARD, uid)
== PackageManager.PERMISSION_GRANTED;
}
+
+ /**
+ * Check if the given UID belongs to the current foreground user. This is
+ * used to prevent apps running in background users from modifying network
+ * configurations.
+ * <p>
+ * UIDs belonging to system internals (such as SystemUI) are always allowed,
+ * since they always run as {@link UserHandle#USER_SYSTEM}.
+ *
+ * @param uid uid of the app.
+ * @return true if the given UID belongs to the current foreground user,
+ * otherwise false.
+ */
+ public boolean doesUidBelongToCurrentUser(int uid) {
+ if (uid == android.os.Process.SYSTEM_UID
+ // UIDs with the NETWORK_SETTINGS permission are always allowed since they are
+ // acting on behalf of the user.
+ || checkNetworkSettingsPermission(uid)) {
+ return true;
+ }
+ boolean isCurrentProfile = isCurrentProfile(uid);
+ if (!isCurrentProfile) {
+ // Fix for b/174749461
+ EventLog.writeEvent(0x534e4554, "174749461", -1,
+ "Non foreground user trying to modify wifi configuration");
+ }
+ return isCurrentProfile;
+ }
}
diff --git a/tests/wifitests/src/com/android/server/wifi/WifiConfigManagerTest.java b/tests/wifitests/src/com/android/server/wifi/WifiConfigManagerTest.java
index ca1b4a07c..dcc3303d1 100644
--- a/tests/wifitests/src/com/android/server/wifi/WifiConfigManagerTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/WifiConfigManagerTest.java
@@ -184,6 +184,7 @@ public class WifiConfigManagerTest {
when(mWifiPermissionsUtil.checkNetworkSettingsPermission(anyInt())).thenReturn(true);
when(mWifiPermissionsWrapper.getDevicePolicyManagerInternal())
.thenReturn(mDevicePolicyManagerInternal);
+ when(mWifiPermissionsUtil.doesUidBelongToCurrentUser(anyInt())).thenReturn(true);
createWifiConfigManager();
mWifiConfigManager.setOnSavedNetworkUpdateListener(mWcmListener);
}
@@ -2253,6 +2254,8 @@ public class WifiConfigManagerTest {
setupStoreDataForUserRead(user2Networks, new HashSet<String>());
// Now switch the user to user 2 and ensure that user 1's private network has been removed.
when(mUserManager.isUserUnlockingOrUnlocked(user2)).thenReturn(true);
+ when(mWifiPermissionsUtil.doesUidBelongToCurrentUser(user1Network.creatorUid))
+ .thenReturn(false);
Set<Integer> removedNetworks = mWifiConfigManager.handleUserSwitch(user2);
verify(mWifiConfigStore).switchUserStoreAndRead(any(WifiConfigStore.StoreFile.class));
assertTrue((removedNetworks.size() == 1) && (removedNetworks.contains(user1NetworkId)));
@@ -2333,7 +2336,7 @@ public class WifiConfigManagerTest {
public void testHandleUserSwitchPushesOtherPrivateNetworksToSharedStore() throws Exception {
int user1 = TEST_DEFAULT_USER;
int user2 = TEST_DEFAULT_USER + 1;
- setupUserProfiles(user2);
+ setupUserProfiles(user1);
int appId = 674;
@@ -2366,6 +2369,8 @@ public class WifiConfigManagerTest {
}
};
setupStoreDataForUserRead(userNetworks, new HashSet<String>());
+ when(mWifiPermissionsUtil.doesUidBelongToCurrentUser(user2Network.creatorUid))
+ .thenReturn(false);
mWifiConfigManager.handleUserUnlock(user1);
verify(mWifiConfigStore).switchUserStoreAndRead(any(WifiConfigStore.StoreFile.class));
// Capture the written data for the user 1 and ensure that it corresponds to what was
@@ -2380,6 +2385,10 @@ public class WifiConfigManagerTest {
// Now switch the user to user2 and ensure that user 2's private network has been moved to
// the user store.
when(mUserManager.isUserUnlockingOrUnlocked(user2)).thenReturn(true);
+ when(mWifiPermissionsUtil.doesUidBelongToCurrentUser(user1Network.creatorUid))
+ .thenReturn(true).thenReturn(false);
+ when(mWifiPermissionsUtil.doesUidBelongToCurrentUser(user2Network.creatorUid))
+ .thenReturn(false).thenReturn(true);
mWifiConfigManager.handleUserSwitch(user2);
// Set the expected network list before comparing. user1Network should be in shared data.
// Note: In the real world, user1Network will no longer be visible now because it should
@@ -2445,6 +2454,8 @@ public class WifiConfigManagerTest {
// Unlock the owner of the legacy Passpoint configuration, verify it is removed from
// the configured networks (migrated to PasspointManager).
setupStoreDataForUserRead(new ArrayList<WifiConfiguration>(), new HashSet<String>());
+ when(mWifiPermissionsUtil.doesUidBelongToCurrentUser(passpointConfig.creatorUid))
+ .thenReturn(false);
mWifiConfigManager.handleUserUnlock(user1);
verify(mWifiConfigStore).switchUserStoreAndRead(any(WifiConfigStore.StoreFile.class));
Pair<List<WifiConfiguration>, List<WifiConfiguration>> writtenNetworkList =
@@ -2572,7 +2583,8 @@ public class WifiConfigManagerTest {
// Ensure that we have 2 networks in the database before the stop.
assertEquals(2, mWifiConfigManager.getConfiguredNetworks().size());
-
+ when(mWifiPermissionsUtil.doesUidBelongToCurrentUser(user1Network.creatorUid))
+ .thenReturn(false);
mWifiConfigManager.handleUserStop(user1);
// Ensure that we only have 1 shared network in the database after the stop.
@@ -2701,6 +2713,8 @@ public class WifiConfigManagerTest {
int creatorUid = UserHandle.getUid(user2, 674);
+ when(mWifiPermissionsUtil.doesUidBelongToCurrentUser(creatorUid)).thenReturn(false);
+
// Create a network for user2 try adding it. This should be rejected.
final WifiConfiguration user2Network = WifiConfigurationTestUtil.createPskNetwork();
NetworkUpdateResult result = addNetworkToWifiConfigManager(user2Network, creatorUid);
diff --git a/tests/wifitests/src/com/android/server/wifi/WifiStateMachineTest.java b/tests/wifitests/src/com/android/server/wifi/WifiStateMachineTest.java
index 8154a02b9..1a5e8c1a1 100644
--- a/tests/wifitests/src/com/android/server/wifi/WifiStateMachineTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/WifiStateMachineTest.java
@@ -1541,13 +1541,13 @@ public class WifiStateMachineTest {
@Test
public void syncRemovePasspointConfig() throws Exception {
String fqdn = "test.com";
- when(mPasspointManager.removeProvider(fqdn)).thenReturn(true);
+ when(mPasspointManager.removeProvider(anyInt(), eq(fqdn))).thenReturn(true);
mLooper.startAutoDispatch();
assertTrue(mWsm.syncRemovePasspointConfig(mWsmAsyncChannel, fqdn));
mLooper.stopAutoDispatch();
reset(mPasspointManager);
- when(mPasspointManager.removeProvider(fqdn)).thenReturn(false);
+ when(mPasspointManager.removeProvider(anyInt(), eq(fqdn))).thenReturn(false);
mLooper.startAutoDispatch();
assertFalse(mWsm.syncRemovePasspointConfig(mWsmAsyncChannel, fqdn));
mLooper.stopAutoDispatch();
diff --git a/tests/wifitests/src/com/android/server/wifi/hotspot2/PasspointManagerTest.java b/tests/wifitests/src/com/android/server/wifi/hotspot2/PasspointManagerTest.java
index 284c7f9b9..2051bdfa2 100644
--- a/tests/wifitests/src/com/android/server/wifi/hotspot2/PasspointManagerTest.java
+++ b/tests/wifitests/src/com/android/server/wifi/hotspot2/PasspointManagerTest.java
@@ -72,6 +72,7 @@ import com.android.server.wifi.hotspot2.anqp.I18Name;
import com.android.server.wifi.hotspot2.anqp.OsuProviderInfo;
import com.android.server.wifi.util.InformationElementUtil.RoamingConsortium;
import com.android.server.wifi.util.ScanResultUtil;
+import com.android.server.wifi.util.WifiPermissionsUtil;
import org.junit.Before;
import org.junit.Test;
@@ -131,7 +132,7 @@ public class PasspointManagerTest {
@Mock IProvisioningCallback mCallback;
@Mock WfaKeyStore mWfaKeyStore;
@Mock KeyStore mKeyStore;
-
+ @Mock WifiPermissionsUtil mWifiPermissionsUtil;
TestLooper mLooper;
PasspointManager mManager;
@@ -152,7 +153,8 @@ public class PasspointManagerTest {
when(mObjectFactory.makePasspointProvisioner(any(Context.class)))
.thenReturn(mPasspointProvisioner);
mManager = new PasspointManager(mContext, mWifiNative, mWifiKeyStore, mClock,
- mSimAccessor, mObjectFactory, mWifiConfigManager, mWifiConfigStore, mWifiMetrics);
+ mSimAccessor, mObjectFactory, mWifiConfigManager, mWifiConfigStore, mWifiMetrics,
+ mWifiPermissionsUtil);
ArgumentCaptor<PasspointEventHandler.Callbacks> callbacks =
ArgumentCaptor.forClass(PasspointEventHandler.Callbacks.class);
verify(mObjectFactory).makePasspointEventHandler(any(WifiNative.class),
@@ -383,7 +385,7 @@ public class PasspointManagerTest {
assertEquals(1, mDataSource.getProviderIndex());
// Remove the provider.
- assertTrue(mManager.removeProvider(TEST_FQDN));
+ assertTrue(mManager.removeProvider(TEST_CREATOR_UID, TEST_FQDN));
verify(provider).uninstallCertsAndKeys();
verify(mWifiConfigManager).saveToStore(true);
verify(mWifiMetrics).incrementNumPasspointProviderUninstallation();
@@ -423,7 +425,7 @@ public class PasspointManagerTest {
assertEquals(1, mDataSource.getProviderIndex());
// Remove the provider.
- assertTrue(mManager.removeProvider(TEST_FQDN));
+ assertTrue(mManager.removeProvider(TEST_CREATOR_UID, TEST_FQDN));
verify(provider).uninstallCertsAndKeys();
verify(mWifiConfigManager).saveToStore(true);
verify(mWifiMetrics).incrementNumPasspointProviderUninstallation();
@@ -543,7 +545,7 @@ public class PasspointManagerTest {
*/
@Test
public void removeNonExistingProvider() throws Exception {
- assertFalse(mManager.removeProvider(TEST_FQDN));
+ assertFalse(mManager.removeProvider(TEST_CREATOR_UID, TEST_FQDN));
verify(mWifiMetrics).incrementNumPasspointProviderUninstallation();
verify(mWifiMetrics, never()).incrementNumPasspointProviderUninstallSuccess();
}