| /* |
| * Copyright (C) 2016 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.server.wifi.util; |
| |
| import android.Manifest; |
| import android.app.AppOpsManager; |
| import android.content.Context; |
| import android.content.pm.PackageManager; |
| import android.content.pm.UserInfo; |
| import android.location.LocationManager; |
| import android.net.NetworkStack; |
| import android.os.Binder; |
| import android.os.Build; |
| import android.os.RemoteException; |
| import android.os.UserHandle; |
| import android.os.UserManager; |
| import android.util.Slog; |
| |
| import com.android.internal.annotations.GuardedBy; |
| import com.android.server.wifi.WifiInjector; |
| import com.android.server.wifi.WifiLog; |
| |
| import java.util.List; |
| |
| /** |
| * A wifi permissions utility assessing permissions |
| * for getting scan results by a package. |
| */ |
| public class WifiPermissionsUtil { |
| private static final String TAG = "WifiPermissionsUtil"; |
| private final WifiPermissionsWrapper mWifiPermissionsWrapper; |
| private final Context mContext; |
| private final AppOpsManager mAppOps; |
| private final UserManager mUserManager; |
| private final Object mLock = new Object(); |
| @GuardedBy("mLock") |
| private LocationManager mLocationManager; |
| private WifiLog mLog; |
| |
| public WifiPermissionsUtil(WifiPermissionsWrapper wifiPermissionsWrapper, |
| Context context, UserManager userManager, WifiInjector wifiInjector) { |
| mWifiPermissionsWrapper = wifiPermissionsWrapper; |
| mContext = context; |
| mUserManager = userManager; |
| mAppOps = (AppOpsManager) mContext.getSystemService(Context.APP_OPS_SERVICE); |
| mLog = wifiInjector.makeLog(TAG); |
| } |
| |
| /** |
| * Checks if the app has the permission to override Wi-Fi network configuration or not. |
| * |
| * @param uid uid of the app. |
| * @return true if the app does have the permission, false otherwise. |
| */ |
| public boolean checkConfigOverridePermission(int uid) { |
| try { |
| int permission = mWifiPermissionsWrapper.getOverrideWifiConfigPermission(uid); |
| return (permission == PackageManager.PERMISSION_GRANTED); |
| } catch (RemoteException e) { |
| mLog.err("Error checking for permission: %").r(e.getMessage()).flush(); |
| return false; |
| } |
| } |
| |
| /** |
| * Checks if the app has the permission to change Wi-Fi network configuration or not. |
| * |
| * @param uid uid of the app. |
| * @return true if the app does have the permission, false otherwise. |
| */ |
| public boolean checkChangePermission(int uid) { |
| try { |
| int permission = mWifiPermissionsWrapper.getChangeWifiConfigPermission(uid); |
| return (permission == PackageManager.PERMISSION_GRANTED); |
| } catch (RemoteException e) { |
| mLog.err("Error checking for permission: %").r(e.getMessage()).flush(); |
| return false; |
| } |
| } |
| |
| /** |
| * Checks if the app has the permission to access Wi-Fi state or not. |
| * |
| * @param uid uid of the app. |
| * @return true if the app does have the permission, false otherwise. |
| */ |
| public boolean checkWifiAccessPermission(int uid) { |
| try { |
| int permission = mWifiPermissionsWrapper.getAccessWifiStatePermission(uid); |
| return (permission == PackageManager.PERMISSION_GRANTED); |
| } catch (RemoteException e) { |
| mLog.err("Error checking for permission: %").r(e.getMessage()).flush(); |
| return false; |
| } |
| } |
| |
| /** |
| * Check and enforce Coarse or Fine Location permission (depending on target SDK). |
| * |
| * @param pkgName PackageName of the application requesting access |
| * @param uid The uid of the package |
| */ |
| public void enforceLocationPermission(String pkgName, int uid) { |
| if (!checkCallersLocationPermission(pkgName, uid, /* coarseForTargetSdkLessThanQ */ true)) { |
| throw new SecurityException( |
| "UID " + uid + " does not have Coarse/Fine Location permission"); |
| } |
| } |
| |
| /** |
| * Checks whether than the target SDK of the package is less than the specified version code. |
| */ |
| public boolean isTargetSdkLessThan(String packageName, int versionCode) { |
| long ident = Binder.clearCallingIdentity(); |
| try { |
| if (mContext.getPackageManager().getApplicationInfo(packageName, 0).targetSdkVersion |
| < versionCode) { |
| return true; |
| } |
| } catch (PackageManager.NameNotFoundException e) { |
| // In case of exception, assume unknown app (more strict checking) |
| // Note: This case will never happen since checkPackage is |
| // called to verify validity before checking App's version. |
| } finally { |
| Binder.restoreCallingIdentity(ident); |
| } |
| return false; |
| } |
| |
| /** |
| * Checks that calling process has android.Manifest.permission.ACCESS_FINE_LOCATION or |
| * android.Manifest.permission.ACCESS_FINE_LOCATION (depending on config/targetSDK leve) |
| * and a corresponding app op is allowed for this package and uid. |
| * |
| * @param pkgName PackageName of the application requesting access |
| * @param uid The uid of the package |
| * @param coarseForTargetSdkLessThanQ If true and the targetSDK < Q then will check for COARSE |
| * else (false or targetSDK >= Q) then will check for FINE |
| */ |
| public boolean checkCallersLocationPermission(String pkgName, int uid, |
| boolean coarseForTargetSdkLessThanQ) { |
| boolean isTargetSdkLessThanQ = isTargetSdkLessThan(pkgName, Build.VERSION_CODES.Q); |
| |
| String permissionType = Manifest.permission.ACCESS_FINE_LOCATION; |
| if (coarseForTargetSdkLessThanQ && isTargetSdkLessThanQ) { |
| // Having FINE permission implies having COARSE permission (but not the reverse) |
| permissionType = Manifest.permission.ACCESS_COARSE_LOCATION; |
| } |
| if (mWifiPermissionsWrapper.getUidPermission(permissionType, uid) |
| == PackageManager.PERMISSION_DENIED) { |
| return false; |
| } |
| |
| // Always checking FINE - even if will not enforce. This will record the request for FINE |
| // so that a location request by the app is surfaced to the user. |
| boolean isAppOpAllowed = noteAppOpAllowed(AppOpsManager.OP_FINE_LOCATION, pkgName, uid); |
| if (!isAppOpAllowed && coarseForTargetSdkLessThanQ && isTargetSdkLessThanQ) { |
| isAppOpAllowed = noteAppOpAllowed(AppOpsManager.OP_COARSE_LOCATION, pkgName, uid); |
| } |
| return isAppOpAllowed; |
| } |
| |
| /** |
| * Check and enforce Fine Location permission. |
| * |
| * @param pkgName PackageName of the application requesting access |
| * @param uid The uid of the package |
| */ |
| public void enforceFineLocationPermission(String pkgName, int uid) { |
| if (!checkCallersFineLocationPermission(pkgName, uid, false)) { |
| throw new SecurityException("UID " + uid + " does not have Fine Location permission"); |
| } |
| } |
| |
| |
| /** |
| * Checks that calling process has android.Manifest.permission.ACCESS_FINE_LOCATION |
| * and a corresponding app op is allowed for this package and uid. |
| * |
| * @param pkgName PackageName of the application requesting access |
| * @param uid The uid of the package |
| * @param hideFromAppOps True to invoke {@link AppOpsManager#checkOp(int, int, String)}, false |
| * to invoke {@link AppOpsManager#noteOp(int, int, String)}. |
| */ |
| private boolean checkCallersFineLocationPermission(String pkgName, int uid, |
| boolean hideFromAppOps) { |
| // Having FINE permission implies having COARSE permission (but not the reverse) |
| if (mWifiPermissionsWrapper.getUidPermission( |
| Manifest.permission.ACCESS_FINE_LOCATION, uid) |
| == PackageManager.PERMISSION_DENIED) { |
| return false; |
| } |
| if (hideFromAppOps) { |
| // Don't note the operation, just check if the app is allowed to perform the operation. |
| if (!checkAppOpAllowed(AppOpsManager.OP_FINE_LOCATION, pkgName, uid)) { |
| return false; |
| } |
| } else { |
| if (!noteAppOpAllowed(AppOpsManager.OP_FINE_LOCATION, pkgName, uid)) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * Checks that calling process has android.Manifest.permission.LOCATION_HARDWARE. |
| * |
| * @param uid The uid of the package |
| */ |
| private boolean checkCallersHardwareLocationPermission(int uid) { |
| return mWifiPermissionsWrapper.getUidPermission(Manifest.permission.LOCATION_HARDWARE, uid) |
| == PackageManager.PERMISSION_GRANTED; |
| } |
| |
| /** |
| * API to determine if the caller has permissions to get scan results. Throws SecurityException |
| * if the caller has no permission. |
| * @param pkgName package name of the application requesting access |
| * @param uid The uid of the package |
| */ |
| public void enforceCanAccessScanResults(String pkgName, int uid) throws SecurityException { |
| checkPackage(uid, pkgName); |
| |
| // Apps with NETWORK_SETTINGS, NETWORK_SETUP_WIZARD, NETWORK_MANAGED_PROVISIONING, |
| // NETWORK_STACK & MAINLINE_NETWORK_STACK are granted a bypass. |
| if (checkNetworkSettingsPermission(uid) || checkNetworkSetupWizardPermission(uid) |
| || checkNetworkManagedProvisioningPermission(uid) |
| || checkNetworkStackPermission(uid) || checkMainlineNetworkStackPermission(uid)) { |
| return; |
| } |
| |
| // Location mode must be enabled |
| if (!isLocationModeEnabled()) { |
| // Location mode is disabled, scan results cannot be returned |
| throw new SecurityException("Location mode is disabled for the device"); |
| } |
| |
| // Check if the calling Uid has CAN_READ_PEER_MAC_ADDRESS permission. |
| boolean canCallingUidAccessLocation = checkCallerHasPeersMacAddressPermission(uid); |
| // LocationAccess by App: caller must have Coarse/Fine Location permission to have access to |
| // location information. |
| boolean canAppPackageUseLocation = checkCallersLocationPermission(pkgName, |
| uid, /* coarseForTargetSdkLessThanQ */ true); |
| |
| // If neither caller or app has location access, there is no need to check |
| // any other permissions. Deny access to scan results. |
| if (!canCallingUidAccessLocation && !canAppPackageUseLocation) { |
| throw new SecurityException("UID " + uid + " has no location permission"); |
| } |
| // Check if Wifi Scan request is an operation allowed for this App. |
| if (!isScanAllowedbyApps(pkgName, uid)) { |
| throw new SecurityException("UID " + uid + " has no wifi scan permission"); |
| } |
| // If the User or profile is current, permission is granted |
| // Otherwise, uid must have INTERACT_ACROSS_USERS_FULL permission. |
| if (!isCurrentProfile(uid) && !checkInteractAcrossUsersFull(uid)) { |
| throw new SecurityException("UID " + uid + " profile not permitted"); |
| } |
| } |
| |
| /** |
| * API to determine if the caller has permissions to get scan results. Throws SecurityException |
| * if the caller has no permission. |
| * @param pkgName package name of the application requesting access |
| * @param uid The uid of the package |
| * @param ignoreLocationSettings Whether this request can bypass location settings. |
| * @param hideFromAppOps Whether to note the request in app-ops logging or not. |
| * |
| * Note: This is to be used for checking permissions in the internal WifiScanner API surface |
| * for requests coming from system apps. |
| */ |
| public void enforceCanAccessScanResultsForWifiScanner( |
| String pkgName, int uid, boolean ignoreLocationSettings, boolean hideFromAppOps) |
| throws SecurityException { |
| checkPackage(uid, pkgName); |
| |
| // Location mode must be enabled |
| if (!isLocationModeEnabled()) { |
| if (ignoreLocationSettings) { |
| mLog.w("Request from " + pkgName + " violated location settings"); |
| } else { |
| // Location mode is disabled, scan results cannot be returned |
| throw new SecurityException("Location mode is disabled for the device"); |
| } |
| } |
| // LocationAccess by App: caller must have fine & hardware Location permission to have |
| // access to location information. |
| if (!checkCallersFineLocationPermission(pkgName, uid, hideFromAppOps) |
| || !checkCallersHardwareLocationPermission(uid)) { |
| throw new SecurityException("UID " + uid + " has no location permission"); |
| } |
| // Check if Wifi Scan request is an operation allowed for this App. |
| if (!isScanAllowedbyApps(pkgName, uid)) { |
| throw new SecurityException("UID " + uid + " has no wifi scan permission"); |
| } |
| } |
| |
| /** |
| * |
| * Checks that calling process has android.Manifest.permission.ACCESS_FINE_LOCATION |
| * and a corresponding app op is allowed for this package and uid |
| * |
| * @param pkgName package name of the application requesting access |
| * @param uid The uid of the package |
| * @param needLocationModeEnabled indicates location mode must be enabled. |
| * |
| * @return true if caller has permission, false otherwise |
| */ |
| public boolean checkCanAccessWifiDirect(String pkgName, int uid, |
| boolean needLocationModeEnabled) { |
| try { |
| checkPackage(uid, pkgName); |
| } catch (SecurityException se) { |
| Slog.e(TAG, "Package check exception - " + se); |
| return false; |
| } |
| |
| // Apps with NETWORK_SETTINGS are granted a bypass. |
| if (checkNetworkSettingsPermission(uid)) { |
| return true; |
| } |
| |
| // Location mode must be enabled if needed. |
| if (needLocationModeEnabled && !isLocationModeEnabled()) { |
| Slog.e(TAG, "Location mode is disabled for the device"); |
| return false; |
| } |
| |
| // LocationAccess by App: caller must have Fine Location permission to have access to |
| // location information. |
| if (!checkCallersLocationPermission(pkgName, uid, |
| /* coarseForTargetSdkLessThanQ */ false)) { |
| Slog.e(TAG, "UID " + uid + " has no location permission"); |
| return false; |
| } |
| return true; |
| } |
| |
| /** |
| * API to check to validate if a package name belongs to a UID. Throws SecurityException |
| * if pkgName does not belongs to a UID |
| * |
| * @param pkgName package name of the application requesting access |
| * @param uid The uid of the package |
| * |
| */ |
| public void checkPackage(int uid, String pkgName) throws SecurityException { |
| if (pkgName == null) { |
| throw new SecurityException("Checking UID " + uid + " but Package Name is Null"); |
| } |
| mAppOps.checkPackage(uid, pkgName); |
| } |
| |
| /** |
| * Returns true if the caller holds PEERS_MAC_ADDRESS permission. |
| */ |
| private boolean checkCallerHasPeersMacAddressPermission(int uid) { |
| return mWifiPermissionsWrapper.getUidPermission( |
| android.Manifest.permission.PEERS_MAC_ADDRESS, uid) |
| == PackageManager.PERMISSION_GRANTED; |
| } |
| |
| /** |
| * Returns true if Wifi scan operation is allowed for this caller |
| * and package. |
| */ |
| private boolean isScanAllowedbyApps(String pkgName, int uid) { |
| return noteAppOpAllowed(AppOpsManager.OP_WIFI_SCAN, pkgName, uid); |
| } |
| |
| /** |
| * Returns true if the caller holds INTERACT_ACROSS_USERS_FULL. |
| */ |
| private boolean checkInteractAcrossUsersFull(int uid) { |
| return mWifiPermissionsWrapper.getUidPermission( |
| android.Manifest.permission.INTERACT_ACROSS_USERS_FULL, uid) |
| == PackageManager.PERMISSION_GRANTED; |
| } |
| |
| /** |
| * Returns true if the calling user is the current one or a profile of the |
| * current user. |
| */ |
| private boolean isCurrentProfile(int uid) { |
| int currentUser = mWifiPermissionsWrapper.getCurrentUser(); |
| int callingUserId = mWifiPermissionsWrapper.getCallingUserId(uid); |
| if (callingUserId == currentUser) { |
| return true; |
| } else { |
| List<UserInfo> userProfiles = mUserManager.getProfiles(currentUser); |
| for (UserInfo user : userProfiles) { |
| if (user.id == callingUserId) { |
| return true; |
| } |
| } |
| } |
| return false; |
| } |
| |
| private boolean noteAppOpAllowed(int op, String pkgName, int uid) { |
| return mAppOps.noteOp(op, uid, pkgName) == AppOpsManager.MODE_ALLOWED; |
| } |
| |
| private boolean checkAppOpAllowed(int op, String pkgName, int uid) { |
| return mAppOps.checkOp(op, uid, pkgName) == AppOpsManager.MODE_ALLOWED; |
| } |
| |
| private boolean retrieveLocationManagerIfNecessary() { |
| // This is going to be accessed by multiple threads. |
| synchronized (mLock) { |
| if (mLocationManager == null) { |
| mLocationManager = |
| (LocationManager) mContext.getSystemService(Context.LOCATION_SERVICE); |
| } |
| } |
| return mLocationManager != null; |
| } |
| |
| /** |
| * Retrieves a handle to LocationManager (if not already done) and check if location is enabled. |
| */ |
| public boolean isLocationModeEnabled() { |
| if (!retrieveLocationManagerIfNecessary()) return false; |
| return mLocationManager.isLocationEnabledForUser(UserHandle.of( |
| mWifiPermissionsWrapper.getCurrentUser())); |
| } |
| |
| /** |
| * Returns true if the |uid| holds NETWORK_SETTINGS permission. |
| */ |
| public boolean checkNetworkSettingsPermission(int uid) { |
| return mWifiPermissionsWrapper.getUidPermission( |
| android.Manifest.permission.NETWORK_SETTINGS, uid) |
| == PackageManager.PERMISSION_GRANTED; |
| } |
| |
| /** |
| * Returns true if the |uid| holds LOCAL_MAC_ADDRESS permission. |
| */ |
| public boolean checkLocalMacAddressPermission(int uid) { |
| return mWifiPermissionsWrapper.getUidPermission( |
| android.Manifest.permission.LOCAL_MAC_ADDRESS, uid) |
| == PackageManager.PERMISSION_GRANTED; |
| } |
| |
| /** |
| * Returns true if the |uid| holds NETWORK_SETUP_WIZARD permission. |
| */ |
| public boolean checkNetworkSetupWizardPermission(int uid) { |
| return mWifiPermissionsWrapper.getUidPermission( |
| android.Manifest.permission.NETWORK_SETUP_WIZARD, uid) |
| == PackageManager.PERMISSION_GRANTED; |
| } |
| |
| /** |
| * Returns true if the |uid| holds NETWORK_STACK permission. |
| */ |
| public boolean checkNetworkStackPermission(int uid) { |
| return mWifiPermissionsWrapper.getUidPermission( |
| android.Manifest.permission.NETWORK_STACK, uid) |
| == PackageManager.PERMISSION_GRANTED; |
| } |
| |
| /** |
| * Returns true if the |uid| holds MAINLINE_NETWORK_STACK permission. |
| */ |
| public boolean checkMainlineNetworkStackPermission(int uid) { |
| return mWifiPermissionsWrapper.getUidPermission( |
| NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK, uid) |
| == PackageManager.PERMISSION_GRANTED; |
| } |
| |
| /** |
| * Returns true if the |uid| holds NETWORK_MANAGED_PROVISIONING permission. |
| */ |
| public boolean checkNetworkManagedProvisioningPermission(int uid) { |
| return mWifiPermissionsWrapper.getUidPermission( |
| android.Manifest.permission.NETWORK_MANAGED_PROVISIONING, uid) |
| == PackageManager.PERMISSION_GRANTED; |
| } |
| |
| /** |
| * Returns true if the |uid| holds NETWORK_CARRIER_PROVISIONING permission. |
| */ |
| public boolean checkNetworkCarrierProvisioningPermission(int uid) { |
| return mWifiPermissionsWrapper.getUidPermission( |
| android.Manifest.permission.NETWORK_CARRIER_PROVISIONING, uid) |
| == PackageManager.PERMISSION_GRANTED; |
| } |
| |
| /** |
| * Returns true if the |callingUid|/\callingPackage| holds SYSTEM_ALERT_WINDOW permission. |
| */ |
| public boolean checkSystemAlertWindowPermission(int callingUid, String callingPackage) { |
| final int mode = mAppOps.noteOp( |
| AppOpsManager.OP_SYSTEM_ALERT_WINDOW, callingUid, callingPackage); |
| if (mode == AppOpsManager.MODE_DEFAULT) { |
| return mWifiPermissionsWrapper.getUidPermission( |
| Manifest.permission.SYSTEM_ALERT_WINDOW, callingUid) |
| == PackageManager.PERMISSION_GRANTED; |
| } |
| return mode == AppOpsManager.MODE_ALLOWED; |
| } |
| } |