1 /* 2 * Copyright (C) 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License 15 */ 16 17 package android.net; 18 19 import android.Manifest; 20 import android.Manifest.permission; 21 import android.annotation.Nullable; 22 import android.content.Context; 23 import android.content.Intent; 24 import android.content.pm.ActivityInfo; 25 import android.content.pm.PackageManager; 26 import android.content.pm.ResolveInfo; 27 import android.os.UserHandle; 28 import android.provider.Settings; 29 import android.text.TextUtils; 30 import android.util.Log; 31 32 import java.util.ArrayList; 33 import java.util.Collection; 34 import java.util.Collections; 35 import java.util.List; 36 37 /** 38 * Internal class for managing the primary network scorer application. 39 * 40 * TODO: Rename this to something more generic. 41 * 42 * @hide 43 */ 44 public final class NetworkScorerAppManager { 45 private static final String TAG = "NetworkScorerAppManager"; 46 47 private static final Intent SCORE_INTENT = 48 new Intent(NetworkScoreManager.ACTION_SCORE_NETWORKS); 49 50 /** This class cannot be instantiated. */ 51 private NetworkScorerAppManager() {} 52 53 public static class NetworkScorerAppData { 54 /** Package name of this scorer app. */ 55 public final String mPackageName; 56 57 /** UID of the scorer app. */ 58 public final int mPackageUid; 59 60 /** Name of this scorer app for display. */ 61 public final CharSequence mScorerName; 62 63 /** 64 * Optional class name of a configuration activity. Null if none is set. 65 * 66 * @see NetworkScoreManager#ACTION_CUSTOM_ENABLE 67 */ 68 public final String mConfigurationActivityClassName; 69 70 /** 71 * Optional class name of the scoring service we can bind to. Null if none is set. 72 */ 73 public final String mScoringServiceClassName; 74 75 public NetworkScorerAppData(String packageName, int packageUid, CharSequence scorerName, 76 @Nullable String configurationActivityClassName, 77 @Nullable String scoringServiceClassName) { 78 mScorerName = scorerName; 79 mPackageName = packageName; 80 mPackageUid = packageUid; 81 mConfigurationActivityClassName = configurationActivityClassName; 82 mScoringServiceClassName = scoringServiceClassName; 83 } 84 85 @Override 86 public String toString() { 87 final StringBuilder sb = new StringBuilder("NetworkScorerAppData{"); 88 sb.append("mPackageName='").append(mPackageName).append('\''); 89 sb.append(", mPackageUid=").append(mPackageUid); 90 sb.append(", mScorerName=").append(mScorerName); 91 sb.append(", mConfigurationActivityClassName='").append(mConfigurationActivityClassName) 92 .append('\''); 93 sb.append(", mScoringServiceClassName='").append(mScoringServiceClassName).append('\''); 94 sb.append('}'); 95 return sb.toString(); 96 } 97 } 98 99 /** 100 * Returns the list of available scorer apps. 101 * 102 * <p>A network scorer is any application which: 103 * <ul> 104 * <li>Declares the {@link android.Manifest.permission#SCORE_NETWORKS} permission. 105 * <li>Includes a receiver for {@link NetworkScoreManager#ACTION_SCORE_NETWORKS} guarded by the 106 * {@link android.Manifest.permission#BROADCAST_NETWORK_PRIVILEGED} permission. 107 * </ul> 108 * 109 * @return the list of scorers, or the empty list if there are no valid scorers. 110 */ 111 public static Collection<NetworkScorerAppData> getAllValidScorers(Context context) { 112 // Network scorer apps can only run as the primary user so exit early if we're not the 113 // primary user. 114 if (UserHandle.getCallingUserId() != UserHandle.USER_SYSTEM) { 115 return Collections.emptyList(); 116 } 117 118 List<NetworkScorerAppData> scorers = new ArrayList<>(); 119 PackageManager pm = context.getPackageManager(); 120 // Only apps installed under the primary user of the device can be scorers. 121 // TODO: http://b/23422763 122 List<ResolveInfo> receivers = 123 pm.queryBroadcastReceiversAsUser(SCORE_INTENT, 0 /* flags */, UserHandle.USER_SYSTEM); 124 for (ResolveInfo receiver : receivers) { 125 // This field is a misnomer, see android.content.pm.ResolveInfo#activityInfo 126 final ActivityInfo receiverInfo = receiver.activityInfo; 127 if (receiverInfo == null) { 128 // Should never happen with queryBroadcastReceivers, but invalid nonetheless. 129 continue; 130 } 131 if (!permission.BROADCAST_NETWORK_PRIVILEGED.equals(receiverInfo.permission)) { 132 // Receiver doesn't require the BROADCAST_NETWORK_PRIVILEGED permission, which 133 // means anyone could trigger network scoring and flood the framework with score 134 // requests. 135 continue; 136 } 137 if (pm.checkPermission(permission.SCORE_NETWORKS, receiverInfo.packageName) != 138 PackageManager.PERMISSION_GRANTED) { 139 // Application doesn't hold the SCORE_NETWORKS permission, so the user never 140 // approved it as a network scorer. 141 continue; 142 } 143 144 // Optionally, this package may specify a configuration activity. 145 String configurationActivityClassName = null; 146 Intent intent = new Intent(NetworkScoreManager.ACTION_CUSTOM_ENABLE); 147 intent.setPackage(receiverInfo.packageName); 148 List<ResolveInfo> configActivities = pm.queryIntentActivities(intent, 0 /* flags */); 149 if (configActivities != null && !configActivities.isEmpty()) { 150 ActivityInfo activityInfo = configActivities.get(0).activityInfo; 151 if (activityInfo != null) { 152 configurationActivityClassName = activityInfo.name; 153 } 154 } 155 156 // Find the scoring service class we can bind to, if any. 157 String scoringServiceClassName = null; 158 Intent serviceIntent = new Intent(NetworkScoreManager.ACTION_SCORE_NETWORKS); 159 serviceIntent.setPackage(receiverInfo.packageName); 160 ResolveInfo resolveServiceInfo = pm.resolveService(serviceIntent, 0 /* flags */); 161 if (resolveServiceInfo != null && resolveServiceInfo.serviceInfo != null) { 162 scoringServiceClassName = resolveServiceInfo.serviceInfo.name; 163 } 164 165 // NOTE: loadLabel will attempt to load the receiver's label and fall back to the 166 // app label if none is present. 167 scorers.add(new NetworkScorerAppData(receiverInfo.packageName, 168 receiverInfo.applicationInfo.uid, receiverInfo.loadLabel(pm), 169 configurationActivityClassName, scoringServiceClassName)); 170 } 171 172 return scorers; 173 } 174 175 /** 176 * Get the application to use for scoring networks. 177 * 178 * @return the scorer app info or null if scoring is disabled (including if no scorer was ever 179 * selected) or if the previously-set scorer is no longer a valid scorer app (e.g. because 180 * it was disabled or uninstalled). 181 */ 182 public static NetworkScorerAppData getActiveScorer(Context context) { 183 String scorerPackage = Settings.Global.getString(context.getContentResolver(), 184 Settings.Global.NETWORK_SCORER_APP); 185 return getScorer(context, scorerPackage); 186 } 187 188 /** 189 * Set the specified package as the default scorer application. 190 * 191 * <p>The caller must have permission to write to {@link android.provider.Settings.Global}. 192 * 193 * @param context the context of the calling application 194 * @param packageName the packageName of the new scorer to use. If null, scoring will be 195 * disabled. Otherwise, the scorer will only be set if it is a valid scorer application. 196 * @return true if the scorer was changed, or false if the package is not a valid scorer. 197 */ 198 public static boolean setActiveScorer(Context context, String packageName) { 199 String oldPackageName = Settings.Global.getString(context.getContentResolver(), 200 Settings.Global.NETWORK_SCORER_APP); 201 if (TextUtils.equals(oldPackageName, packageName)) { 202 // No change. 203 return true; 204 } 205 206 Log.i(TAG, "Changing network scorer from " + oldPackageName + " to " + packageName); 207 208 if (packageName == null) { 209 Settings.Global.putString(context.getContentResolver(), 210 Settings.Global.NETWORK_SCORER_APP, null); 211 return true; 212 } else { 213 // We only make the change if the new package is valid. 214 if (getScorer(context, packageName) != null) { 215 Settings.Global.putString(context.getContentResolver(), 216 Settings.Global.NETWORK_SCORER_APP, packageName); 217 return true; 218 } else { 219 Log.w(TAG, "Requested network scorer is not valid: " + packageName); 220 return false; 221 } 222 } 223 } 224 225 /** Determine whether the application with the given UID is the enabled scorer. */ 226 public static boolean isCallerActiveScorer(Context context, int callingUid) { 227 NetworkScorerAppData defaultApp = getActiveScorer(context); 228 if (defaultApp == null) { 229 return false; 230 } 231 if (callingUid != defaultApp.mPackageUid) { 232 return false; 233 } 234 // To be extra safe, ensure the caller holds the SCORE_NETWORKS permission. It always 235 // should, since it couldn't become the active scorer otherwise, but this can't hurt. 236 return context.checkCallingPermission(Manifest.permission.SCORE_NETWORKS) == 237 PackageManager.PERMISSION_GRANTED; 238 } 239 240 /** Returns the {@link NetworkScorerAppData} for the given app, or null if it's not a scorer. */ 241 public static NetworkScorerAppData getScorer(Context context, String packageName) { 242 if (TextUtils.isEmpty(packageName)) { 243 return null; 244 } 245 Collection<NetworkScorerAppData> applications = getAllValidScorers(context); 246 for (NetworkScorerAppData app : applications) { 247 if (packageName.equals(app.mPackageName)) { 248 return app; 249 } 250 } 251 return null; 252 } 253 } 254
