| /* |
| * Copyright (C) 2017 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; |
| |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| import android.content.Context; |
| import android.database.ContentObserver; |
| import android.net.NetworkKey; |
| import android.net.NetworkScoreManager; |
| import android.net.NetworkScorerAppData; |
| import android.net.wifi.ScanResult; |
| import android.net.wifi.WifiConfiguration; |
| import android.net.wifi.WifiNetworkScoreCache; |
| import android.os.Handler; |
| import android.os.Looper; |
| import android.os.Process; |
| import android.provider.Settings; |
| import android.text.TextUtils; |
| import android.util.LocalLog; |
| import android.util.Log; |
| |
| import com.android.server.wifi.WifiNetworkSelector.NetworkEvaluator.OnConnectableListener; |
| import com.android.server.wifi.util.ScanResultUtil; |
| import com.android.server.wifi.util.WifiPermissionsUtil; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| /** |
| * {@link WifiNetworkSelector.NetworkEvaluator} implementation that uses scores obtained by |
| * {@link NetworkScoreManager#requestScores(NetworkKey[])} to make network connection decisions. |
| */ |
| public class ScoredNetworkEvaluator implements WifiNetworkSelector.NetworkEvaluator { |
| private static final String TAG = "ScoredNetworkEvaluator"; |
| private static final boolean DEBUG = Log.isLoggable(TAG, Log.DEBUG); |
| |
| private final NetworkScoreManager mNetworkScoreManager; |
| private final WifiConfigManager mWifiConfigManager; |
| private final LocalLog mLocalLog; |
| private final ContentObserver mContentObserver; |
| private final WifiPermissionsUtil mWifiPermissionsUtil; |
| private boolean mNetworkRecommendationsEnabled; |
| private WifiNetworkScoreCache mScoreCache; |
| |
| ScoredNetworkEvaluator(final Context context, Looper looper, |
| final FrameworkFacade frameworkFacade, NetworkScoreManager networkScoreManager, |
| WifiConfigManager wifiConfigManager, LocalLog localLog, |
| WifiNetworkScoreCache wifiNetworkScoreCache, |
| WifiPermissionsUtil wifiPermissionsUtil) { |
| mScoreCache = wifiNetworkScoreCache; |
| mWifiPermissionsUtil = wifiPermissionsUtil; |
| mNetworkScoreManager = networkScoreManager; |
| mWifiConfigManager = wifiConfigManager; |
| mLocalLog = localLog; |
| mContentObserver = new ContentObserver(new Handler(looper)) { |
| @Override |
| public void onChange(boolean selfChange) { |
| mNetworkRecommendationsEnabled = frameworkFacade.getIntegerSetting(context, |
| Settings.Global.NETWORK_RECOMMENDATIONS_ENABLED, 0) == 1; |
| } |
| }; |
| frameworkFacade.registerContentObserver(context, |
| Settings.Global.getUriFor(Settings.Global.NETWORK_RECOMMENDATIONS_ENABLED), |
| false /* notifyForDescendents */, mContentObserver); |
| mContentObserver.onChange(false /* unused */); |
| mLocalLog.log("ScoredNetworkEvaluator constructed. mNetworkRecommendationsEnabled: " |
| + mNetworkRecommendationsEnabled); |
| } |
| |
| @Override |
| public void update(List<ScanDetail> scanDetails) { |
| if (mNetworkRecommendationsEnabled) { |
| updateNetworkScoreCache(scanDetails); |
| } |
| } |
| |
| private void updateNetworkScoreCache(List<ScanDetail> scanDetails) { |
| ArrayList<NetworkKey> unscoredNetworks = new ArrayList<NetworkKey>(); |
| for (int i = 0; i < scanDetails.size(); i++) { |
| ScanResult scanResult = scanDetails.get(i).getScanResult(); |
| NetworkKey networkKey = NetworkKey.createFromScanResult(scanResult); |
| if (networkKey != null) { |
| // Is there a ScoredNetwork for this ScanResult? If not, request a score. |
| if (mScoreCache.getScoredNetwork(networkKey) == null) { |
| unscoredNetworks.add(networkKey); |
| } |
| } |
| } |
| |
| // Kick the score manager if there are any unscored network. |
| if (!unscoredNetworks.isEmpty() && activeScorerAllowedtoSeeScanResults()) { |
| NetworkKey[] unscoredNetworkKeys = |
| unscoredNetworks.toArray(new NetworkKey[unscoredNetworks.size()]); |
| mNetworkScoreManager.requestScores(unscoredNetworkKeys); |
| } |
| } |
| |
| private boolean activeScorerAllowedtoSeeScanResults() { |
| NetworkScorerAppData networkScorerAppData = mNetworkScoreManager.getActiveScorer(); |
| String packageName = mNetworkScoreManager.getActiveScorerPackage(); |
| if (networkScorerAppData == null || packageName == null) return false; |
| int uid = networkScorerAppData.packageUid; |
| try { |
| mWifiPermissionsUtil.enforceCanAccessScanResults(packageName, uid); |
| return true; |
| } catch (SecurityException e) { |
| return false; |
| } |
| } |
| |
| @Override |
| public WifiConfiguration evaluateNetworks(List<ScanDetail> scanDetails, |
| WifiConfiguration currentNetwork, String currentBssid, boolean connected, |
| boolean untrustedNetworkAllowed, |
| @NonNull OnConnectableListener onConnectableListener) { |
| if (!mNetworkRecommendationsEnabled) { |
| mLocalLog.log("Skipping evaluateNetworks; Network recommendations disabled."); |
| return null; |
| } |
| |
| final ScoreTracker scoreTracker = new ScoreTracker(); |
| for (int i = 0; i < scanDetails.size(); i++) { |
| ScanDetail scanDetail = scanDetails.get(i); |
| ScanResult scanResult = scanDetail.getScanResult(); |
| if (scanResult == null) continue; |
| if (mWifiConfigManager.wasEphemeralNetworkDeleted( |
| ScanResultUtil.createQuotedSSID(scanResult.SSID))) { |
| debugLog("Ignoring disabled ephemeral SSID: " + scanResult.SSID); |
| continue; |
| } |
| final WifiConfiguration configuredNetwork = |
| mWifiConfigManager.getConfiguredNetworkForScanDetailAndCache(scanDetail); |
| boolean untrustedScanResult = configuredNetwork == null || !configuredNetwork.trusted; |
| |
| if (!untrustedNetworkAllowed && untrustedScanResult) { |
| continue; |
| } |
| |
| // Track scan results for open wifi networks |
| if (configuredNetwork == null) { |
| if (ScanResultUtil.isScanResultForOpenNetwork(scanResult)) { |
| scoreTracker.trackUntrustedCandidate(scanDetail); |
| } |
| continue; |
| } |
| |
| // Ignore trusted and non-externally scored networks |
| if (configuredNetwork.trusted && !configuredNetwork.useExternalScores) { |
| continue; |
| } |
| |
| // Ignore externally scored or ephemeral networks that have been disabled for selection |
| if (!configuredNetwork.getNetworkSelectionStatus().isNetworkEnabled()) { |
| debugLog("Ignoring disabled SSID: " + configuredNetwork.SSID); |
| continue; |
| } |
| |
| // TODO(b/37485956): consider applying a boost for networks with only the same SSID |
| boolean isCurrentNetwork = currentNetwork != null |
| && currentNetwork.networkId == configuredNetwork.networkId |
| && TextUtils.equals(currentBssid, scanResult.BSSID); |
| if (!configuredNetwork.trusted) { |
| scoreTracker.trackUntrustedCandidate( |
| scanResult, configuredNetwork, isCurrentNetwork); |
| } else { |
| scoreTracker.trackExternallyScoredCandidate( |
| scanResult, configuredNetwork, isCurrentNetwork); |
| } |
| onConnectableListener.onConnectable(scanDetail, configuredNetwork, 0); |
| } |
| |
| |
| return scoreTracker.getCandidateConfiguration(onConnectableListener); |
| } |
| |
| /** Used to track the network with the highest score. */ |
| class ScoreTracker { |
| private static final int EXTERNAL_SCORED_NONE = 0; |
| private static final int EXTERNAL_SCORED_SAVED_NETWORK = 1; |
| private static final int EXTERNAL_SCORED_UNTRUSTED_NETWORK = 2; |
| |
| private int mBestCandidateType = EXTERNAL_SCORED_NONE; |
| private int mHighScore = WifiNetworkScoreCache.INVALID_NETWORK_SCORE; |
| private WifiConfiguration mEphemeralConfig; |
| private WifiConfiguration mSavedConfig; |
| private ScanResult mScanResultCandidate; |
| private ScanDetail mScanDetailCandidate; |
| |
| /** |
| * Returns the available external network score or null if no score is available. |
| * |
| * @param scanResult The scan result of the network to score. |
| * @param isCurrentNetwork Flag which indicates whether this is the current network. |
| * @return A valid external score if one is available or NULL. |
| */ |
| @Nullable |
| private Integer getNetworkScore(ScanResult scanResult, boolean isCurrentNetwork) { |
| if (mScoreCache.isScoredNetwork(scanResult)) { |
| int score = mScoreCache.getNetworkScore(scanResult, isCurrentNetwork); |
| if (DEBUG) { |
| mLocalLog.log(WifiNetworkSelector.toScanId(scanResult) + " has score: " |
| + score + " isCurrentNetwork network: " + isCurrentNetwork); |
| } |
| return score; |
| } |
| return null; |
| } |
| |
| /** Track an untrusted {@link ScanDetail}. */ |
| void trackUntrustedCandidate(ScanDetail scanDetail) { |
| ScanResult scanResult = scanDetail.getScanResult(); |
| Integer score = getNetworkScore(scanResult, false /* isCurrentNetwork */); |
| if (score != null && score > mHighScore) { |
| mHighScore = score; |
| mScanResultCandidate = scanResult; |
| mScanDetailCandidate = scanDetail; |
| mBestCandidateType = EXTERNAL_SCORED_UNTRUSTED_NETWORK; |
| debugLog(WifiNetworkSelector.toScanId(scanResult) |
| + " becomes the new untrusted candidate."); |
| } |
| } |
| |
| /** |
| * Track an untrusted {@link ScanResult} that already has a corresponding |
| * ephemeral {@link WifiConfiguration}. |
| */ |
| void trackUntrustedCandidate( |
| ScanResult scanResult, WifiConfiguration config, boolean isCurrentNetwork) { |
| Integer score = getNetworkScore(scanResult, isCurrentNetwork); |
| if (score != null && score > mHighScore) { |
| mHighScore = score; |
| mScanResultCandidate = scanResult; |
| mScanDetailCandidate = null; |
| mBestCandidateType = EXTERNAL_SCORED_UNTRUSTED_NETWORK; |
| mEphemeralConfig = config; |
| mWifiConfigManager.setNetworkCandidateScanResult(config.networkId, scanResult, 0); |
| debugLog(WifiNetworkSelector.toScanId(scanResult) |
| + " becomes the new untrusted candidate."); |
| } |
| } |
| |
| /** Tracks a saved network that has been marked with useExternalScores */ |
| void trackExternallyScoredCandidate( |
| ScanResult scanResult, WifiConfiguration config, boolean isCurrentNetwork) { |
| // Always take the highest score. If there's a tie and an untrusted network is currently |
| // the best then pick the saved network. |
| Integer score = getNetworkScore(scanResult, isCurrentNetwork); |
| if (score != null |
| && (score > mHighScore |
| || (mBestCandidateType == EXTERNAL_SCORED_UNTRUSTED_NETWORK |
| && score == mHighScore))) { |
| mHighScore = score; |
| mSavedConfig = config; |
| mScanResultCandidate = scanResult; |
| mScanDetailCandidate = null; |
| mBestCandidateType = EXTERNAL_SCORED_SAVED_NETWORK; |
| mWifiConfigManager.setNetworkCandidateScanResult(config.networkId, scanResult, 0); |
| debugLog(WifiNetworkSelector.toScanId(scanResult) |
| + " becomes the new externally scored saved network candidate."); |
| } |
| } |
| |
| /** Returns the best candidate network tracked by this {@link ScoreTracker}. */ |
| @Nullable |
| WifiConfiguration getCandidateConfiguration( |
| @NonNull OnConnectableListener onConnectableListener) { |
| int candidateNetworkId = WifiConfiguration.INVALID_NETWORK_ID; |
| switch (mBestCandidateType) { |
| case ScoreTracker.EXTERNAL_SCORED_UNTRUSTED_NETWORK: |
| if (mEphemeralConfig != null) { |
| candidateNetworkId = mEphemeralConfig.networkId; |
| mLocalLog.log(String.format("existing ephemeral candidate %s network ID:%d" |
| + ", meteredHint=%b", |
| WifiNetworkSelector.toScanId(mScanResultCandidate), |
| candidateNetworkId, |
| mEphemeralConfig.meteredHint)); |
| break; |
| } |
| |
| mEphemeralConfig = |
| ScanResultUtil.createNetworkFromScanResult(mScanResultCandidate); |
| // Mark this config as ephemeral so it isn't persisted. |
| mEphemeralConfig.ephemeral = true; |
| // Mark this network as untrusted. |
| mEphemeralConfig.trusted = false; |
| mEphemeralConfig.meteredHint = mScoreCache.getMeteredHint(mScanResultCandidate); |
| NetworkUpdateResult result = |
| mWifiConfigManager.addOrUpdateNetwork(mEphemeralConfig, |
| Process.WIFI_UID); |
| if (!result.isSuccess()) { |
| mLocalLog.log("Failed to add ephemeral network"); |
| break; |
| } |
| if (!mWifiConfigManager.updateNetworkSelectionStatus(result.getNetworkId(), |
| WifiConfiguration.NetworkSelectionStatus.NETWORK_SELECTION_ENABLE)) { |
| mLocalLog.log("Failed to make ephemeral network selectable"); |
| break; |
| } |
| candidateNetworkId = result.getNetworkId(); |
| if (mScanDetailCandidate == null) { |
| // This should never happen, but if it does, WNS will log a wtf. |
| // A message here might help with the diagnosis. |
| Log.e(TAG, "mScanDetailCandidate is null!"); |
| } |
| mWifiConfigManager.setNetworkCandidateScanResult(candidateNetworkId, |
| mScanResultCandidate, 0); |
| mLocalLog.log(String.format("new ephemeral candidate %s network ID:%d, " |
| + "meteredHint=%b", |
| WifiNetworkSelector.toScanId(mScanResultCandidate), |
| candidateNetworkId, |
| mEphemeralConfig.meteredHint)); |
| break; |
| case ScoreTracker.EXTERNAL_SCORED_SAVED_NETWORK: |
| candidateNetworkId = mSavedConfig.networkId; |
| mLocalLog.log(String.format("new saved network candidate %s network ID:%d", |
| WifiNetworkSelector.toScanId(mScanResultCandidate), |
| candidateNetworkId)); |
| break; |
| case ScoreTracker.EXTERNAL_SCORED_NONE: |
| default: |
| mLocalLog.log("ScoredNetworkEvaluator did not see any good candidates."); |
| break; |
| } |
| WifiConfiguration ans = mWifiConfigManager.getConfiguredNetwork( |
| candidateNetworkId); |
| if (ans != null && mScanDetailCandidate != null) { |
| // This is a newly created config, so we need to call onConnectable. |
| onConnectableListener.onConnectable(mScanDetailCandidate, ans, 0); |
| } |
| return ans; |
| } |
| } |
| |
| private void debugLog(String msg) { |
| if (DEBUG) { |
| mLocalLog.log(msg); |
| } |
| } |
| |
| @Override |
| public @EvaluatorId int getId() { |
| return EVALUATOR_ID_SCORED; |
| } |
| |
| @Override |
| public String getName() { |
| return TAG; |
| } |
| } |