com/android/server/wifi/SavedNetworkEvaluator.java - platform/prebuilts/fullsdk/sources/android-29 - Git at Google

 /*
  * 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;

 import android.annotation.NonNull;
 import android.content.Context;
 import android.net.wifi.ScanResult;
 import android.net.wifi.WifiConfiguration;
 import android.telephony.SubscriptionManager;
 import android.util.LocalLog;

 import com.android.internal.R;
 import com.android.internal.annotations.VisibleForTesting;
 import com.android.server.wifi.util.TelephonyUtil;

 import java.util.List;

 /**
  * This class is the WifiNetworkSelector.NetworkEvaluator implementation for
  * saved networks.
  */
 public class SavedNetworkEvaluator implements WifiNetworkSelector.NetworkEvaluator {
     private static final String NAME = "SavedNetworkEvaluator";
     private final WifiConfigManager mWifiConfigManager;
     private final Clock mClock;
     private final LocalLog mLocalLog;
     private final WifiConnectivityHelper mConnectivityHelper;
     private final SubscriptionManager mSubscriptionManager;
     private final int mRssiScoreSlope;
     private final int mRssiScoreOffset;
     private final int mSameBssidAward;
     private final int mSameNetworkAward;
     private final int mBand5GHzAward;
     private final int mLastSelectionAward;
     private final int mSecurityAward;
     private final ScoringParams mScoringParams;

     /**
      * Time it takes for the mLastSelectionAward to decay by one point, in milliseconds
      */
     @VisibleForTesting
     public static final int LAST_SELECTION_AWARD_DECAY_MSEC = 60 * 1000;


     SavedNetworkEvaluator(final Context context, ScoringParams scoringParams,
             WifiConfigManager configManager, Clock clock,
             LocalLog localLog, WifiConnectivityHelper connectivityHelper,
             SubscriptionManager subscriptionManager) {
         mScoringParams = scoringParams;
         mWifiConfigManager = configManager;
         mClock = clock;
         mLocalLog = localLog;
         mConnectivityHelper = connectivityHelper;
         mSubscriptionManager = subscriptionManager;

         mRssiScoreSlope = context.getResources().getInteger(
                 R.integer.config_wifi_framework_RSSI_SCORE_SLOPE);
         mRssiScoreOffset = context.getResources().getInteger(
                 R.integer.config_wifi_framework_RSSI_SCORE_OFFSET);
         mSameBssidAward = context.getResources().getInteger(
                 R.integer.config_wifi_framework_SAME_BSSID_AWARD);
         mSameNetworkAward = context.getResources().getInteger(
                 R.integer.config_wifi_framework_current_network_boost);
         mLastSelectionAward = context.getResources().getInteger(
                 R.integer.config_wifi_framework_LAST_SELECTION_AWARD);
         mSecurityAward = context.getResources().getInteger(
                 R.integer.config_wifi_framework_SECURITY_AWARD);
         mBand5GHzAward = context.getResources().getInteger(
                 R.integer.config_wifi_framework_5GHz_preference_boost_factor);
     }

     private void localLog(String log) {
         mLocalLog.log(log);
     }

     /**
      * Get the evaluator type.
      */
     @Override
     public @EvaluatorId int getId() {
         return EVALUATOR_ID_SAVED;
     }

     /**
      * Get the evaluator name.
      */
     @Override
     public String getName() {
         return NAME;
     }

     /**
      * Update the evaluator.
      */
     @Override
     public void update(List<ScanDetail> scanDetails) { }

     private int calculateBssidScore(ScanResult scanResult, WifiConfiguration network,
                         WifiConfiguration currentNetwork, String currentBssid,
                         StringBuffer sbuf) {
         int score = 0;
         boolean is5GHz = scanResult.is5GHz();

         sbuf.append("[ ").append(scanResult.SSID).append(" ").append(scanResult.BSSID)
                 .append(" RSSI:").append(scanResult.level).append(" ] ");
         // Calculate the RSSI score.
         int rssiSaturationThreshold = mScoringParams.getGoodRssi(scanResult.frequency);
         int rssi = Math.min(scanResult.level, rssiSaturationThreshold);
         score += (rssi + mRssiScoreOffset) * mRssiScoreSlope;
         sbuf.append(" RSSI score: ").append(score).append(",");

         // 5GHz band bonus.
         if (is5GHz) {
             score += mBand5GHzAward;
             sbuf.append(" 5GHz bonus: ").append(mBand5GHzAward).append(",");
         }

         // Last user selection award.
         int lastUserSelectedNetworkId = mWifiConfigManager.getLastSelectedNetwork();
         if (lastUserSelectedNetworkId != WifiConfiguration.INVALID_NETWORK_ID
                 && lastUserSelectedNetworkId == network.networkId) {
             long timeDifference = mClock.getElapsedSinceBootMillis()
                     - mWifiConfigManager.getLastSelectedTimeStamp();
             if (timeDifference > 0) {
                 int decay = (int) (timeDifference / LAST_SELECTION_AWARD_DECAY_MSEC);
                 int bonus = Math.max(mLastSelectionAward - decay, 0);
                 score += bonus;
                 sbuf.append(" User selection ").append(timeDifference)
                         .append(" ms ago, bonus: ").append(bonus).append(",");
             }
         }

         // Same network award.
         if (currentNetwork != null && network.networkId == currentNetwork.networkId) {
             score += mSameNetworkAward;
             sbuf.append(" Same network bonus: ").append(mSameNetworkAward).append(",");

             // When firmware roaming is supported, equivalent BSSIDs (the ones under the
             // same network as the currently connected one) get the same BSSID award.
             if (mConnectivityHelper.isFirmwareRoamingSupported()
                     && currentBssid != null && !currentBssid.equals(scanResult.BSSID)) {
                 score += mSameBssidAward;
                 sbuf.append(" Equivalent BSSID bonus: ").append(mSameBssidAward).append(",");
             }
         }

         // Same BSSID award.
         if (currentBssid != null && currentBssid.equals(scanResult.BSSID)) {
             score += mSameBssidAward;
             sbuf.append(" Same BSSID bonus: ").append(mSameBssidAward).append(",");
         }

         // Security award.
         if (!WifiConfigurationUtil.isConfigForOpenNetwork(network)) {
             score += mSecurityAward;
             sbuf.append(" Secure network bonus: ").append(mSecurityAward).append(",");
         }

         sbuf.append(" ## Total score: ").append(score).append("\n");

         return score;
     }

     /**
      * Evaluate all the networks from the scan results and return
      * the WifiConfiguration of the network chosen for connection.
      *
      * @return configuration of the chosen network;
      *         null if no network in this category is available.
      */
     @Override
     public WifiConfiguration evaluateNetworks(List<ScanDetail> scanDetails,
                     WifiConfiguration currentNetwork, String currentBssid, boolean connected,
                     boolean untrustedNetworkAllowed,
                     @NonNull OnConnectableListener onConnectableListener) {
         int highestScore = Integer.MIN_VALUE;
         ScanResult scanResultCandidate = null;
         WifiConfiguration candidate = null;
         StringBuffer scoreHistory = new StringBuffer();

         for (ScanDetail scanDetail : scanDetails) {
             ScanResult scanResult = scanDetail.getScanResult();

             // One ScanResult can be associated with more than one network, hence we calculate all
             // the scores and use the highest one as the ScanResult's score.
             // TODO(b/112196799): this has side effects, rather not do that in an evaluator
             WifiConfiguration network =
                     mWifiConfigManager.getConfiguredNetworkForScanDetailAndCache(scanDetail);

             if (network == null) {
                 continue;
             }

             /**
              * Ignore Passpoint and Ephemeral networks. They are configured networks,
              * but without being persisted to the storage. They are evaluated by
              * {@link PasspointNetworkEvaluator} and {@link ScoredNetworkEvaluator}
              * respectively.
              */
             if (network.isPasspoint() || network.isEphemeral()) {
                 continue;
             }

             WifiConfiguration.NetworkSelectionStatus status =
                     network.getNetworkSelectionStatus();
             // TODO (b/112196799): another side effect
             status.setSeenInLastQualifiedNetworkSelection(true);

             if (!status.isNetworkEnabled()) {
                 continue;
             } else if (network.BSSID != null &&  !network.BSSID.equals("any")
                     && !network.BSSID.equals(scanResult.BSSID)) {
                 // App has specified the only BSSID to connect for this
                 // configuration. So only the matching ScanResult can be a candidate.
                 localLog("Network " + WifiNetworkSelector.toNetworkString(network)
                         + " has specified BSSID " + network.BSSID + ". Skip "
                         + scanResult.BSSID);
                 continue;
             } else if (TelephonyUtil.isSimConfig(network)
                     && !TelephonyUtil.isSimPresent(mSubscriptionManager)) {
                 // Don't select if security type is EAP SIM/AKA/AKA' when SIM is not present.
                 continue;
             }

             int score = calculateBssidScore(scanResult, network, currentNetwork, currentBssid,
                     scoreHistory);

             // Set candidate ScanResult for all saved networks to ensure that users can
             // override network selection. See WifiNetworkSelector#setUserConnectChoice.
             if (score > status.getCandidateScore()
                     || (score == status.getCandidateScore()
                         && status.getCandidate() != null
                         && scanResult.level > status.getCandidate().level)) {
                 mWifiConfigManager.setNetworkCandidateScanResult(
                         network.networkId, scanResult, score);
             }

             // If the network is marked to use external scores, or is an open network with
             // curate saved open networks enabled, do not consider it for network selection.
             if (network.useExternalScores) {
                 localLog("Network " + WifiNetworkSelector.toNetworkString(network)
                         + " has external score.");
                 continue;
             }

             onConnectableListener.onConnectable(scanDetail,
                     mWifiConfigManager.getConfiguredNetwork(network.networkId), score);

             // TODO(b/112196799) - pull into common code
             if (score > highestScore
                     || (score == highestScore
                     && scanResultCandidate != null
                     && scanResult.level > scanResultCandidate.level)) {
                 highestScore = score;
                 scanResultCandidate = scanResult;
                 mWifiConfigManager.setNetworkCandidateScanResult(
                         network.networkId, scanResultCandidate, highestScore);
                 // Reload the network config with the updated info.
                 candidate = mWifiConfigManager.getConfiguredNetwork(network.networkId);
             }
         }

         if (scoreHistory.length() > 0) {
             localLog("\n" + scoreHistory.toString());
         }

         if (scanResultCandidate == null) {
             localLog("did not see any good candidates.");
         }
         return candidate;
     }
 }
	/*
	* 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;

	import android.annotation.NonNull;
	import android.content.Context;
	import android.net.wifi.ScanResult;
	import android.net.wifi.WifiConfiguration;
	import android.telephony.SubscriptionManager;
	import android.util.LocalLog;

	import com.android.internal.R;
	import com.android.internal.annotations.VisibleForTesting;
	import com.android.server.wifi.util.TelephonyUtil;

	import java.util.List;

	/**
	* This class is the WifiNetworkSelector.NetworkEvaluator implementation for
	* saved networks.
	*/
	public class SavedNetworkEvaluator implements WifiNetworkSelector.NetworkEvaluator {
	private static final String NAME = "SavedNetworkEvaluator";
	private final WifiConfigManager mWifiConfigManager;
	private final Clock mClock;
	private final LocalLog mLocalLog;
	private final WifiConnectivityHelper mConnectivityHelper;
	private final SubscriptionManager mSubscriptionManager;
	private final int mRssiScoreSlope;
	private final int mRssiScoreOffset;
	private final int mSameBssidAward;
	private final int mSameNetworkAward;
	private final int mBand5GHzAward;
	private final int mLastSelectionAward;
	private final int mSecurityAward;
	private final ScoringParams mScoringParams;

	/**
	* Time it takes for the mLastSelectionAward to decay by one point, in milliseconds
	*/
	@VisibleForTesting
	public static final int LAST_SELECTION_AWARD_DECAY_MSEC = 60 * 1000;


	SavedNetworkEvaluator(final Context context, ScoringParams scoringParams,
	WifiConfigManager configManager, Clock clock,
	LocalLog localLog, WifiConnectivityHelper connectivityHelper,
	SubscriptionManager subscriptionManager) {
	mScoringParams = scoringParams;
	mWifiConfigManager = configManager;
	mClock = clock;
	mLocalLog = localLog;
	mConnectivityHelper = connectivityHelper;
	mSubscriptionManager = subscriptionManager;

	mRssiScoreSlope = context.getResources().getInteger(
	R.integer.config_wifi_framework_RSSI_SCORE_SLOPE);
	mRssiScoreOffset = context.getResources().getInteger(
	R.integer.config_wifi_framework_RSSI_SCORE_OFFSET);
	mSameBssidAward = context.getResources().getInteger(
	R.integer.config_wifi_framework_SAME_BSSID_AWARD);
	mSameNetworkAward = context.getResources().getInteger(
	R.integer.config_wifi_framework_current_network_boost);
	mLastSelectionAward = context.getResources().getInteger(
	R.integer.config_wifi_framework_LAST_SELECTION_AWARD);
	mSecurityAward = context.getResources().getInteger(
	R.integer.config_wifi_framework_SECURITY_AWARD);
	mBand5GHzAward = context.getResources().getInteger(
	R.integer.config_wifi_framework_5GHz_preference_boost_factor);
	}

	private void localLog(String log) {
	mLocalLog.log(log);
	}

	/**
	* Get the evaluator type.
	*/
	@Override
	public @EvaluatorId int getId() {
	return EVALUATOR_ID_SAVED;
	}

	/**
	* Get the evaluator name.
	*/
	@Override
	public String getName() {
	return NAME;
	}

	/**
	* Update the evaluator.
	*/
	@Override
	public void update(List<ScanDetail> scanDetails) { }

	private int calculateBssidScore(ScanResult scanResult, WifiConfiguration network,
	WifiConfiguration currentNetwork, String currentBssid,
	StringBuffer sbuf) {
	int score = 0;
	boolean is5GHz = scanResult.is5GHz();

	sbuf.append("[ ").append(scanResult.SSID).append(" ").append(scanResult.BSSID)
	.append(" RSSI:").append(scanResult.level).append(" ] ");
	// Calculate the RSSI score.
	int rssiSaturationThreshold = mScoringParams.getGoodRssi(scanResult.frequency);
	int rssi = Math.min(scanResult.level, rssiSaturationThreshold);
	score += (rssi + mRssiScoreOffset) * mRssiScoreSlope;
	sbuf.append(" RSSI score: ").append(score).append(",");

	// 5GHz band bonus.
	if (is5GHz) {
	score += mBand5GHzAward;
	sbuf.append(" 5GHz bonus: ").append(mBand5GHzAward).append(",");
	}

	// Last user selection award.
	int lastUserSelectedNetworkId = mWifiConfigManager.getLastSelectedNetwork();
	if (lastUserSelectedNetworkId != WifiConfiguration.INVALID_NETWORK_ID
	&& lastUserSelectedNetworkId == network.networkId) {
	long timeDifference = mClock.getElapsedSinceBootMillis()
	- mWifiConfigManager.getLastSelectedTimeStamp();
	if (timeDifference > 0) {
	int decay = (int) (timeDifference / LAST_SELECTION_AWARD_DECAY_MSEC);
	int bonus = Math.max(mLastSelectionAward - decay, 0);
	score += bonus;
	sbuf.append(" User selection ").append(timeDifference)
	.append(" ms ago, bonus: ").append(bonus).append(",");
	}
	}

	// Same network award.
	if (currentNetwork != null && network.networkId == currentNetwork.networkId) {
	score += mSameNetworkAward;
	sbuf.append(" Same network bonus: ").append(mSameNetworkAward).append(",");

	// When firmware roaming is supported, equivalent BSSIDs (the ones under the
	// same network as the currently connected one) get the same BSSID award.
	if (mConnectivityHelper.isFirmwareRoamingSupported()
	&& currentBssid != null && !currentBssid.equals(scanResult.BSSID)) {
	score += mSameBssidAward;
	sbuf.append(" Equivalent BSSID bonus: ").append(mSameBssidAward).append(",");
	}
	}

	// Same BSSID award.
	if (currentBssid != null && currentBssid.equals(scanResult.BSSID)) {
	score += mSameBssidAward;
	sbuf.append(" Same BSSID bonus: ").append(mSameBssidAward).append(",");
	}

	// Security award.
	if (!WifiConfigurationUtil.isConfigForOpenNetwork(network)) {
	score += mSecurityAward;
	sbuf.append(" Secure network bonus: ").append(mSecurityAward).append(",");
	}

	sbuf.append(" ## Total score: ").append(score).append("\n");

	return score;
	}

	/**
	* Evaluate all the networks from the scan results and return
	* the WifiConfiguration of the network chosen for connection.
	*
	* @return configuration of the chosen network;
	* null if no network in this category is available.
	*/
	@Override
	public WifiConfiguration evaluateNetworks(List<ScanDetail> scanDetails,
	WifiConfiguration currentNetwork, String currentBssid, boolean connected,
	boolean untrustedNetworkAllowed,
	@NonNull OnConnectableListener onConnectableListener) {
	int highestScore = Integer.MIN_VALUE;
	ScanResult scanResultCandidate = null;
	WifiConfiguration candidate = null;
	StringBuffer scoreHistory = new StringBuffer();

	for (ScanDetail scanDetail : scanDetails) {
	ScanResult scanResult = scanDetail.getScanResult();

	// One ScanResult can be associated with more than one network, hence we calculate all
	// the scores and use the highest one as the ScanResult's score.
	// TODO(b/112196799): this has side effects, rather not do that in an evaluator
	WifiConfiguration network =
	mWifiConfigManager.getConfiguredNetworkForScanDetailAndCache(scanDetail);

	if (network == null) {
	continue;
	}

	/**
	* Ignore Passpoint and Ephemeral networks. They are configured networks,
	* but without being persisted to the storage. They are evaluated by
	* {@link PasspointNetworkEvaluator} and {@link ScoredNetworkEvaluator}
	* respectively.
	*/
	if (network.isPasspoint() \|\| network.isEphemeral()) {
	continue;
	}

	WifiConfiguration.NetworkSelectionStatus status =
	network.getNetworkSelectionStatus();
	// TODO (b/112196799): another side effect
	status.setSeenInLastQualifiedNetworkSelection(true);

	if (!status.isNetworkEnabled()) {
	continue;
	} else if (network.BSSID != null && !network.BSSID.equals("any")
	&& !network.BSSID.equals(scanResult.BSSID)) {
	// App has specified the only BSSID to connect for this
	// configuration. So only the matching ScanResult can be a candidate.
	localLog("Network " + WifiNetworkSelector.toNetworkString(network)
	+ " has specified BSSID " + network.BSSID + ". Skip "
	+ scanResult.BSSID);
	continue;
	} else if (TelephonyUtil.isSimConfig(network)
	&& !TelephonyUtil.isSimPresent(mSubscriptionManager)) {
	// Don't select if security type is EAP SIM/AKA/AKA' when SIM is not present.
	continue;
	}

	int score = calculateBssidScore(scanResult, network, currentNetwork, currentBssid,
	scoreHistory);

	// Set candidate ScanResult for all saved networks to ensure that users can
	// override network selection. See WifiNetworkSelector#setUserConnectChoice.
	if (score > status.getCandidateScore()
	\|\| (score == status.getCandidateScore()
	&& status.getCandidate() != null
	&& scanResult.level > status.getCandidate().level)) {
	mWifiConfigManager.setNetworkCandidateScanResult(
	network.networkId, scanResult, score);
	}

	// If the network is marked to use external scores, or is an open network with
	// curate saved open networks enabled, do not consider it for network selection.
	if (network.useExternalScores) {
	localLog("Network " + WifiNetworkSelector.toNetworkString(network)
	+ " has external score.");
	continue;
	}

	onConnectableListener.onConnectable(scanDetail,
	mWifiConfigManager.getConfiguredNetwork(network.networkId), score);

	// TODO(b/112196799) - pull into common code
	if (score > highestScore
	\|\| (score == highestScore
	&& scanResultCandidate != null
	&& scanResult.level > scanResultCandidate.level)) {
	highestScore = score;
	scanResultCandidate = scanResult;
	mWifiConfigManager.setNetworkCandidateScanResult(
	network.networkId, scanResultCandidate, highestScore);
	// Reload the network config with the updated info.
	candidate = mWifiConfigManager.getConfiguredNetwork(network.networkId);
	}
	}

	if (scoreHistory.length() > 0) {
	localLog("\n" + scoreHistory.toString());
	}

	if (scanResultCandidate == null) {
	localLog("did not see any good candidates.");
	}
	return candidate;
	}
	}