service/java/com/android/server/wifi/SoftApBackupRestore.java - platform/packages/modules/Wifi - Git at Google

 /*
  * Copyright (C) 2019 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.content.Context;
 import android.net.MacAddress;
 import android.net.wifi.SoftApConfiguration;
 import android.net.wifi.WifiConfiguration;
 import android.net.wifi.WifiMigration;
 import android.util.BackupUtils;
 import android.util.Log;
 import android.util.SparseIntArray;

 import com.android.modules.utils.build.SdkLevel;
 import com.android.server.wifi.util.ApConfigUtil;
 import com.android.server.wifi.util.SettingsMigrationDataHolder;

 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;

 /**
  * Class used to backup/restore data using the SettingsBackupAgent.
  * There are 2 symmetric API's exposed here:
  * 1. retrieveBackupDataFromSoftApConfiguration: Retrieve the configuration data to be backed up.
  * 2. retrieveSoftApConfigurationFromBackupData: Restore the configuration using the provided data.
  * The byte stream to be backed up is versioned to migrate the data easily across
  * revisions.
  */
 public class SoftApBackupRestore {
     private static final String TAG = "SoftApBackupRestore";

     /**
      * Current backup data version.
      */
     private static final int CURRENT_SAP_BACKUP_DATA_VERSION = 8;
     private static final int LAST_SAP_BACKUP_DATA_VERSION_IN_R = 7;

     private static final int ETHER_ADDR_LEN = 6; // Byte array size of MacAddress

     private final Context mContext;
     private final SettingsMigrationDataHolder mSettingsMigrationDataHolder;

     public SoftApBackupRestore(Context context,
             SettingsMigrationDataHolder settingsMigrationDataHolder) {
         mContext = context;
         mSettingsMigrationDataHolder = settingsMigrationDataHolder;
     }

     /**
      * Retrieve a byte stream representing the data that needs to be backed up from the
      * provided softap configuration.
      *
      * @param config saved soft ap config that needs to be backed up.
      * @return Raw byte stream that needs to be backed up.
      */
     public byte[] retrieveBackupDataFromSoftApConfiguration(SoftApConfiguration config) {
         if (config == null) {
             Log.e(TAG, "Invalid configuration received");
             return new byte[0];
         }
         ByteArrayOutputStream baos = new ByteArrayOutputStream();
         try {
             DataOutputStream out = new DataOutputStream(baos);
             if (SdkLevel.isAtLeastS()) {
                 out.writeInt(CURRENT_SAP_BACKUP_DATA_VERSION);
             } else {
                 out.writeInt(LAST_SAP_BACKUP_DATA_VERSION_IN_R);
             }
             BackupUtils.writeString(out, config.getSsid());
             out.writeInt(config.getBand());
             out.writeInt(config.getChannel());
             BackupUtils.writeString(out, config.getPassphrase());
             out.writeInt(config.getSecurityType());
             out.writeBoolean(config.isHiddenSsid());
             out.writeInt(config.getMaxNumberOfClients());
             out.writeLong(config.getShutdownTimeoutMillis());
             out.writeBoolean(config.isClientControlByUserEnabled());
             writeMacAddressList(out, config.getBlockedClientList());
             writeMacAddressList(out, config.getAllowedClientList());
             out.writeBoolean(config.isAutoShutdownEnabled());
             if (SdkLevel.isAtLeastS()) {
                 out.writeBoolean(config.isBridgedModeOpportunisticShutdownEnabled());
                 out.writeInt(config.getMacRandomizationSetting());
                 SparseIntArray channels = config.getChannels();
                 int numOfChannels = channels.size();
                 out.writeInt(numOfChannels);
                 for (int i = 0; i < numOfChannels; i++) {
                     out.writeInt(channels.keyAt(i));
                     out.writeInt(channels.valueAt(i));
                 }
                 out.writeBoolean(config.isIeee80211axEnabled());
             }

         } catch (IOException io) {
             Log.e(TAG, "Invalid configuration received, IOException " + io);
             return new byte[0];
         }
         return baos.toByteArray();
     }

     /**
      * Parse out the configurations from the back up data.
      *
      * @param data raw byte stream representing the data.
      * @return Soft ap config retrieved from the backed up data.
      */
     public SoftApConfiguration retrieveSoftApConfigurationFromBackupData(byte[] data) {
         if (data == null || data.length == 0) {
             Log.e(TAG, "Invalid backup data received");
             return null;
         }
         SoftApConfiguration.Builder configBuilder = new SoftApConfiguration.Builder();
         try {
             DataInputStream in = new DataInputStream(new ByteArrayInputStream(data));
             int version = in.readInt();
             if (version < 1 || version > CURRENT_SAP_BACKUP_DATA_VERSION) {
                 throw new BackupUtils.BadVersionException("Unknown Backup Serialization Version");
             }

             if (version == 1) return null; // Version 1 is a bad dataset.

             configBuilder.setSsid(BackupUtils.readString(in));

             int band;
             if (version < 4) {
                 band = ApConfigUtil.convertWifiConfigBandToSoftApConfigBand(in.readInt());
             } else {
                 band = in.readInt();
             }
             int channel = in.readInt();

             if (channel == 0) {
                 configBuilder.setBand(band);
             } else {
                 configBuilder.setChannel(channel, band);
             }
             String passphrase = BackupUtils.readString(in);
             int securityType = in.readInt();
             if (version < 4 && securityType == WifiConfiguration.KeyMgmt.WPA2_PSK) {
                 configBuilder.setPassphrase(passphrase, SoftApConfiguration.SECURITY_TYPE_WPA2_PSK);
             } else if (version >= 4 && securityType != SoftApConfiguration.SECURITY_TYPE_OPEN) {
                 configBuilder.setPassphrase(passphrase, securityType);
             }
             if (version >= 3) {
                 configBuilder.setHiddenSsid(in.readBoolean());
             }
             if (version >= 5) {
                 configBuilder.setMaxNumberOfClients(in.readInt());
                 if (version >= 7) {
                     configBuilder.setShutdownTimeoutMillis(in.readLong());
                 } else {
                     configBuilder.setShutdownTimeoutMillis(Long.valueOf(in.readInt()));
                 }
                 configBuilder.setClientControlByUserEnabled(in.readBoolean());
                 int numberOfBlockedClient = in.readInt();
                 List<MacAddress> blockedList = new ArrayList<>(
                         macAddressListFromByteArray(in, numberOfBlockedClient));
                 int numberOfAllowedClient = in.readInt();
                 List<MacAddress> allowedList = new ArrayList<>(
                         macAddressListFromByteArray(in, numberOfAllowedClient));
                 configBuilder.setBlockedClientList(blockedList);
                 configBuilder.setAllowedClientList(allowedList);
             }
             if (version >= 6) {
                 configBuilder.setAutoShutdownEnabled(in.readBoolean());
             } else {
                 // Migrate data out of settings.
                 WifiMigration.SettingsMigrationData migrationData =
                         mSettingsMigrationDataHolder.retrieveData();
                 if (migrationData == null) {
                     Log.e(TAG, "No migration data present");
                 } else {
                     configBuilder.setAutoShutdownEnabled(migrationData.isSoftApTimeoutEnabled());
                 }
             }
             if (version >= 8 && SdkLevel.isAtLeastS()) {
                 configBuilder.setBridgedModeOpportunisticShutdownEnabled(in.readBoolean());
                 configBuilder.setMacRandomizationSetting(in.readInt());
                 int numOfChannels = in.readInt();
                 SparseIntArray channels = new SparseIntArray(numOfChannels);
                 for (int i = 0; i < numOfChannels; i++) {
                     channels.put(in.readInt(), in.readInt());
                 }
                 configBuilder.setChannels(channels);
                 configBuilder.setIeee80211axEnabled(in.readBoolean());
             }
         } catch (IOException io) {
             Log.e(TAG, "Invalid backup data received, IOException: " + io);
             return null;
         } catch (BackupUtils.BadVersionException badVersion) {
             Log.e(TAG, "Invalid backup data received, BadVersionException: " + badVersion);
             return null;
         } catch (IllegalArgumentException ie) {
             Log.e(TAG, "Invalid backup data received, IllegalArgumentException " + ie);
             return null;
         }
         return configBuilder.build();
     }

     private void writeMacAddressList(DataOutputStream out, List<MacAddress> macList)
             throws IOException {
         out.writeInt(macList.size());
         Iterator<MacAddress> iterator = macList.iterator();
         while (iterator.hasNext()) {
             byte[] mac = iterator.next().toByteArray();
             out.write(mac, 0, ETHER_ADDR_LEN);
         }
     }

     private List<MacAddress> macAddressListFromByteArray(DataInputStream in, int numberOfClients)
             throws IOException {
         List<MacAddress> macList = new ArrayList<>();
         for (int i = 0; i < numberOfClients; i++) {
             byte[] mac = new byte[ETHER_ADDR_LEN];
             in.read(mac, 0, ETHER_ADDR_LEN);
             macList.add(MacAddress.fromBytes(mac));
         }
         return macList;
     }
 }
	/*
	* Copyright (C) 2019 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.content.Context;
	import android.net.MacAddress;
	import android.net.wifi.SoftApConfiguration;
	import android.net.wifi.WifiConfiguration;
	import android.net.wifi.WifiMigration;
	import android.util.BackupUtils;
	import android.util.Log;
	import android.util.SparseIntArray;

	import com.android.modules.utils.build.SdkLevel;
	import com.android.server.wifi.util.ApConfigUtil;
	import com.android.server.wifi.util.SettingsMigrationDataHolder;

	import java.io.ByteArrayInputStream;
	import java.io.ByteArrayOutputStream;
	import java.io.DataInputStream;
	import java.io.DataOutputStream;
	import java.io.IOException;
	import java.util.ArrayList;
	import java.util.Iterator;
	import java.util.List;

	/**
	* Class used to backup/restore data using the SettingsBackupAgent.
	* There are 2 symmetric API's exposed here:
	* 1. retrieveBackupDataFromSoftApConfiguration: Retrieve the configuration data to be backed up.
	* 2. retrieveSoftApConfigurationFromBackupData: Restore the configuration using the provided data.
	* The byte stream to be backed up is versioned to migrate the data easily across
	* revisions.
	*/
	public class SoftApBackupRestore {
	private static final String TAG = "SoftApBackupRestore";

	/**
	* Current backup data version.
	*/
	private static final int CURRENT_SAP_BACKUP_DATA_VERSION = 8;
	private static final int LAST_SAP_BACKUP_DATA_VERSION_IN_R = 7;

	private static final int ETHER_ADDR_LEN = 6; // Byte array size of MacAddress

	private final Context mContext;
	private final SettingsMigrationDataHolder mSettingsMigrationDataHolder;

	public SoftApBackupRestore(Context context,
	SettingsMigrationDataHolder settingsMigrationDataHolder) {
	mContext = context;
	mSettingsMigrationDataHolder = settingsMigrationDataHolder;
	}

	/**
	* Retrieve a byte stream representing the data that needs to be backed up from the
	* provided softap configuration.
	*
	* @param config saved soft ap config that needs to be backed up.
	* @return Raw byte stream that needs to be backed up.
	*/
	public byte[] retrieveBackupDataFromSoftApConfiguration(SoftApConfiguration config) {
	if (config == null) {
	Log.e(TAG, "Invalid configuration received");
	return new byte[0];
	}
	ByteArrayOutputStream baos = new ByteArrayOutputStream();
	try {
	DataOutputStream out = new DataOutputStream(baos);
	if (SdkLevel.isAtLeastS()) {
	out.writeInt(CURRENT_SAP_BACKUP_DATA_VERSION);
	} else {
	out.writeInt(LAST_SAP_BACKUP_DATA_VERSION_IN_R);
	}
	BackupUtils.writeString(out, config.getSsid());
	out.writeInt(config.getBand());
	out.writeInt(config.getChannel());
	BackupUtils.writeString(out, config.getPassphrase());
	out.writeInt(config.getSecurityType());
	out.writeBoolean(config.isHiddenSsid());
	out.writeInt(config.getMaxNumberOfClients());
	out.writeLong(config.getShutdownTimeoutMillis());
	out.writeBoolean(config.isClientControlByUserEnabled());
	writeMacAddressList(out, config.getBlockedClientList());
	writeMacAddressList(out, config.getAllowedClientList());
	out.writeBoolean(config.isAutoShutdownEnabled());
	if (SdkLevel.isAtLeastS()) {
	out.writeBoolean(config.isBridgedModeOpportunisticShutdownEnabled());
	out.writeInt(config.getMacRandomizationSetting());
	SparseIntArray channels = config.getChannels();
	int numOfChannels = channels.size();
	out.writeInt(numOfChannels);
	for (int i = 0; i < numOfChannels; i++) {
	out.writeInt(channels.keyAt(i));
	out.writeInt(channels.valueAt(i));
	}
	out.writeBoolean(config.isIeee80211axEnabled());
	}

	} catch (IOException io) {
	Log.e(TAG, "Invalid configuration received, IOException " + io);
	return new byte[0];
	}
	return baos.toByteArray();
	}

	/**
	* Parse out the configurations from the back up data.
	*
	* @param data raw byte stream representing the data.
	* @return Soft ap config retrieved from the backed up data.
	*/
	public SoftApConfiguration retrieveSoftApConfigurationFromBackupData(byte[] data) {
	if (data == null \|\| data.length == 0) {
	Log.e(TAG, "Invalid backup data received");
	return null;
	}
	SoftApConfiguration.Builder configBuilder = new SoftApConfiguration.Builder();
	try {
	DataInputStream in = new DataInputStream(new ByteArrayInputStream(data));
	int version = in.readInt();
	if (version < 1 \|\| version > CURRENT_SAP_BACKUP_DATA_VERSION) {
	throw new BackupUtils.BadVersionException("Unknown Backup Serialization Version");
	}

	if (version == 1) return null; // Version 1 is a bad dataset.

	configBuilder.setSsid(BackupUtils.readString(in));

	int band;
	if (version < 4) {
	band = ApConfigUtil.convertWifiConfigBandToSoftApConfigBand(in.readInt());
	} else {
	band = in.readInt();
	}
	int channel = in.readInt();

	if (channel == 0) {
	configBuilder.setBand(band);
	} else {
	configBuilder.setChannel(channel, band);
	}
	String passphrase = BackupUtils.readString(in);
	int securityType = in.readInt();
	if (version < 4 && securityType == WifiConfiguration.KeyMgmt.WPA2_PSK) {
	configBuilder.setPassphrase(passphrase, SoftApConfiguration.SECURITY_TYPE_WPA2_PSK);
	} else if (version >= 4 && securityType != SoftApConfiguration.SECURITY_TYPE_OPEN) {
	configBuilder.setPassphrase(passphrase, securityType);
	}
	if (version >= 3) {
	configBuilder.setHiddenSsid(in.readBoolean());
	}
	if (version >= 5) {
	configBuilder.setMaxNumberOfClients(in.readInt());
	if (version >= 7) {
	configBuilder.setShutdownTimeoutMillis(in.readLong());
	} else {
	configBuilder.setShutdownTimeoutMillis(Long.valueOf(in.readInt()));
	}
	configBuilder.setClientControlByUserEnabled(in.readBoolean());
	int numberOfBlockedClient = in.readInt();
	List<MacAddress> blockedList = new ArrayList<>(
	macAddressListFromByteArray(in, numberOfBlockedClient));
	int numberOfAllowedClient = in.readInt();
	List<MacAddress> allowedList = new ArrayList<>(
	macAddressListFromByteArray(in, numberOfAllowedClient));
	configBuilder.setBlockedClientList(blockedList);
	configBuilder.setAllowedClientList(allowedList);
	}
	if (version >= 6) {
	configBuilder.setAutoShutdownEnabled(in.readBoolean());
	} else {
	// Migrate data out of settings.
	WifiMigration.SettingsMigrationData migrationData =
	mSettingsMigrationDataHolder.retrieveData();
	if (migrationData == null) {
	Log.e(TAG, "No migration data present");
	} else {
	configBuilder.setAutoShutdownEnabled(migrationData.isSoftApTimeoutEnabled());
	}
	}
	if (version >= 8 && SdkLevel.isAtLeastS()) {
	configBuilder.setBridgedModeOpportunisticShutdownEnabled(in.readBoolean());
	configBuilder.setMacRandomizationSetting(in.readInt());
	int numOfChannels = in.readInt();
	SparseIntArray channels = new SparseIntArray(numOfChannels);
	for (int i = 0; i < numOfChannels; i++) {
	channels.put(in.readInt(), in.readInt());
	}
	configBuilder.setChannels(channels);
	configBuilder.setIeee80211axEnabled(in.readBoolean());
	}
	} catch (IOException io) {
	Log.e(TAG, "Invalid backup data received, IOException: " + io);
	return null;
	} catch (BackupUtils.BadVersionException badVersion) {
	Log.e(TAG, "Invalid backup data received, BadVersionException: " + badVersion);
	return null;
	} catch (IllegalArgumentException ie) {
	Log.e(TAG, "Invalid backup data received, IllegalArgumentException " + ie);
	return null;
	}
	return configBuilder.build();
	}

	private void writeMacAddressList(DataOutputStream out, List<MacAddress> macList)
	throws IOException {
	out.writeInt(macList.size());
	Iterator<MacAddress> iterator = macList.iterator();
	while (iterator.hasNext()) {
	byte[] mac = iterator.next().toByteArray();
	out.write(mac, 0, ETHER_ADDR_LEN);
	}
	}

	private List<MacAddress> macAddressListFromByteArray(DataInputStream in, int numberOfClients)
	throws IOException {
	List<MacAddress> macList = new ArrayList<>();
	for (int i = 0; i < numberOfClients; i++) {
	byte[] mac = new byte[ETHER_ADDR_LEN];
	in.read(mac, 0, ETHER_ADDR_LEN);
	macList.add(MacAddress.fromBytes(mac));
	}
	return macList;
	}
	}