src/com/android/managedprovisioning/parser/PropertiesProvisioningDataParser.java - platform/packages/apps/ManagedProvisioning - Git at Google

 /*
  * Copyright 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.managedprovisioning.parser;

 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_ADMIN_EXTRAS_BUNDLE;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_COMPONENT_NAME;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_MINIMUM_VERSION_CODE;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_CHECKSUM;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_DOWNLOAD_COOKIE_HEADER;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_DOWNLOAD_LOCATION;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_NAME;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_SIGNATURE_CHECKSUM;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_LEAVE_ALL_SYSTEM_APPS_ENABLED;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_LOCALE;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_LOCAL_TIME;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_SKIP_ENCRYPTION;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_TIME_ZONE;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_HIDDEN;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_PAC_URL;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_PASSWORD;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_PROXY_BYPASS;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_PROXY_HOST;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_PROXY_PORT;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_SECURITY_TYPE;
 import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_SSID;
 import static android.app.admin.DevicePolicyManager.MIME_TYPE_PROVISIONING_NFC;
 import static android.nfc.NfcAdapter.ACTION_NDEF_DISCOVERED;
 import static com.android.internal.util.Preconditions.checkNotNull;
 import static java.nio.charset.StandardCharsets.UTF_8;

 import android.content.ComponentName;
 import android.content.Context;
 import android.content.Intent;
 import android.nfc.NdefMessage;
 import android.nfc.NdefRecord;
 import android.nfc.NfcAdapter;
 import android.os.Parcelable;
 import android.os.PersistableBundle;
 import android.support.annotation.Nullable;
 import android.support.annotation.VisibleForTesting;

 import com.android.managedprovisioning.ProvisionLogger;
 import com.android.managedprovisioning.common.IllegalProvisioningArgumentException;
 import com.android.managedprovisioning.common.Utils;
 import com.android.managedprovisioning.model.PackageDownloadInfo;
 import com.android.managedprovisioning.model.ProvisioningParams;
 import com.android.managedprovisioning.model.WifiInfo;

 import java.io.IOException;
 import java.io.StringReader;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.IllformedLocaleException;
 import java.util.Locale;
 import java.util.Properties;
 import java.util.Set;


 /**
  * A parser which parses provisioning data from intent which stores in {@link Properties}.
  *
  * <p>It is used to parse an intent contains the extra {@link NfcAdapter.EXTRA_NDEF_MESSAGES}, which
  * indicates that provisioning was started via Nfc bump. This extra contains an NDEF message, which
  * contains an NfcRecord with mime type {@link MIME_TYPE_PROVISIONING_NFC}. This record stores a
  * serialized properties object, which contains the serialized extras described in the next option.
  * A typical use case would be a programmer application that sends an Nfc bump to start Nfc
  * provisioning from a programmer device.
  */
 @VisibleForTesting
 public class PropertiesProvisioningDataParser implements ProvisioningDataParser {

     private final Utils mUtils;

     PropertiesProvisioningDataParser(Utils utils) {
         mUtils = checkNotNull(utils);
     }

     public ProvisioningParams parse(Intent nfcIntent, Context context)
             throws IllegalProvisioningArgumentException {
         if (!ACTION_NDEF_DISCOVERED.equals(nfcIntent.getAction())) {
             throw new IllegalProvisioningArgumentException(
                     "Only NFC action is supported in this parser.");
         }

         ProvisionLogger.logi("Processing Nfc Payload.");
         NdefRecord firstRecord = getFirstNdefRecord(nfcIntent);
         if (firstRecord != null) {
             try {
                 Properties props = new Properties();
                 props.load(new StringReader(new String(firstRecord.getPayload(), UTF_8)));

                 // For parsing non-string parameters.
                 String s = null;

                 ProvisioningParams.Builder builder = ProvisioningParams.Builder.builder()
                         .setStartedByTrustedSource(true)
                         .setProvisioningAction(mUtils.mapIntentToDpmAction(nfcIntent))
                         .setDeviceAdminPackageName(props.getProperty(
                                 EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_NAME));
                 if ((s = props.getProperty(EXTRA_PROVISIONING_DEVICE_ADMIN_COMPONENT_NAME))
                         != null) {
                     builder.setDeviceAdminComponentName(ComponentName.unflattenFromString(s));
                 }

                 // Parse time zone, locale and local time.
                 builder.setTimeZone(props.getProperty(EXTRA_PROVISIONING_TIME_ZONE))
                         .setLocale(MessageParser.stringToLocale(
                                 props.getProperty(EXTRA_PROVISIONING_LOCALE)));
                 if ((s = props.getProperty(EXTRA_PROVISIONING_LOCAL_TIME)) != null) {
                     builder.setLocalTime(Long.parseLong(s));
                 }

                 // Parse WiFi configuration.
                 builder.setWifiInfo(parseWifiInfoFromProperties(props))
                         // Parse device admin package download info.
                         .setDeviceAdminDownloadInfo(parsePackageDownloadInfoFromProperties(props))
                         // Parse EMM customized key-value pairs.
                         // Note: EXTRA_PROVISIONING_ADMIN_EXTRAS_BUNDLE property contains a
                         // Properties object serialized into String. See Properties.store() and
                         // Properties.load() for more details. The property value is optional.
                         .setAdminExtrasBundle(deserializeExtrasBundle(props,
                                 EXTRA_PROVISIONING_ADMIN_EXTRAS_BUNDLE));
                 if ((s = props.getProperty(EXTRA_PROVISIONING_LEAVE_ALL_SYSTEM_APPS_ENABLED))
                         != null) {
                     builder.setLeaveAllSystemAppsEnabled(Boolean.parseBoolean(s));
                 }
                 if ((s = props.getProperty(EXTRA_PROVISIONING_SKIP_ENCRYPTION)) != null) {
                     builder.setSkipEncryption(Boolean.parseBoolean(s));
                 }
                 ProvisionLogger.logi("End processing Nfc Payload.");
                 return builder.build();
             } catch (IOException e) {
                 throw new IllegalProvisioningArgumentException("Couldn't load payload", e);
             } catch (NumberFormatException e) {
                 throw new IllegalProvisioningArgumentException("Incorrect numberformat.", e);
             } catch (IllformedLocaleException e) {
                 throw new IllegalProvisioningArgumentException("Invalid locale.", e);
             } catch (IllegalArgumentException e) {
                 throw new IllegalProvisioningArgumentException("Invalid parameter found!", e);
             } catch (NullPointerException e) {
                 throw new IllegalProvisioningArgumentException(
                         "Compulsory parameter not found!", e);
             }
         }
         throw new IllegalProvisioningArgumentException(
                 "Intent does not contain NfcRecord with the correct MIME type.");
     }

     /**
      * Parses Wifi configuration from an {@link Properties} and returns the result in
      * {@link WifiInfo}.
      */
     @Nullable
     private WifiInfo parseWifiInfoFromProperties(Properties props) {
         if (props.getProperty(EXTRA_PROVISIONING_WIFI_SSID) == null) {
             return null;
         }
         WifiInfo.Builder builder = WifiInfo.Builder.builder()
                 .setSsid(props.getProperty(EXTRA_PROVISIONING_WIFI_SSID))
                 .setSecurityType(props.getProperty(EXTRA_PROVISIONING_WIFI_SECURITY_TYPE))
                 .setPassword(props.getProperty(EXTRA_PROVISIONING_WIFI_PASSWORD))
                 .setProxyHost(props.getProperty(EXTRA_PROVISIONING_WIFI_PROXY_HOST))
                 .setProxyBypassHosts(props.getProperty(EXTRA_PROVISIONING_WIFI_PROXY_BYPASS))
                 .setPacUrl(props.getProperty(EXTRA_PROVISIONING_WIFI_PAC_URL));
         // For parsing non-string parameters.
         String s = null;
         if ((s = props.getProperty(EXTRA_PROVISIONING_WIFI_PROXY_PORT)) != null) {
             builder.setProxyPort(Integer.parseInt(s));
         }
         if ((s = props.getProperty(EXTRA_PROVISIONING_WIFI_HIDDEN)) != null) {
             builder.setHidden(Boolean.parseBoolean(s));
         }

         return builder.build();
     }

     /**
      * Parses device admin package download info from an {@link Properties} and returns the result
      * in {@link PackageDownloadInfo}.
      */
     @Nullable
     private PackageDownloadInfo parsePackageDownloadInfoFromProperties(Properties props) {
         if (props.getProperty(EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_DOWNLOAD_LOCATION) == null) {
             return null;
         }
         PackageDownloadInfo.Builder builder = PackageDownloadInfo.Builder.builder()
                 .setLocation(props.getProperty(
                         EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_DOWNLOAD_LOCATION))
                 .setCookieHeader(props.getProperty(
                         EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_DOWNLOAD_COOKIE_HEADER));
         // For parsing non-string parameters.
         String s = null;
         if ((s = props.getProperty(EXTRA_PROVISIONING_DEVICE_ADMIN_MINIMUM_VERSION_CODE)) != null) {
             builder.setMinVersion(Integer.parseInt(s));
         }
         if ((s = props.getProperty(EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_CHECKSUM)) != null) {
             // Still support SHA-1 for device admin package hash if we are provisioned by a Nfc
             // programmer.
             // TODO: remove once SHA-1 is fully deprecated.
             builder.setPackageChecksum(mUtils.stringToByteArray(s))
                     .setPackageChecksumSupportsSha1(true);
         }
         if ((s = props.getProperty(EXTRA_PROVISIONING_DEVICE_ADMIN_SIGNATURE_CHECKSUM))
                 != null) {
             builder.setSignatureChecksum(mUtils.stringToByteArray(s));
         }
         return builder.build();
     }

     /**
      * Get a {@link PersistableBundle} from a String property in a Properties object.
      * @param props the source of the extra
      * @param extraName key into the Properties object
      * @return the bundle or {@code null} if there was no property with the given name
      * @throws IOException if there was an error parsing the propery
      */
     private PersistableBundle deserializeExtrasBundle(Properties props, String extraName)
             throws IOException {
         PersistableBundle extrasBundle = null;
         String serializedExtras = props.getProperty(extraName);
         if (serializedExtras != null) {
             Properties extrasProp = new Properties();
             extrasProp.load(new StringReader(serializedExtras));
             extrasBundle = new PersistableBundle(extrasProp.size());
             for (String propName : extrasProp.stringPropertyNames()) {
                 extrasBundle.putString(propName, extrasProp.getProperty(propName));
             }
         }
         return extrasBundle;
     }

     /**
      * @return the first {@link NdefRecord} found with a recognized MIME-type
      */
     private NdefRecord getFirstNdefRecord(Intent nfcIntent) {
         // Only one first message with NFC_MIME_TYPE is used.
         for (Parcelable rawMsg : nfcIntent.getParcelableArrayExtra(
                 NfcAdapter.EXTRA_NDEF_MESSAGES)) {
             NdefMessage msg = (NdefMessage) rawMsg;
             for (NdefRecord record : msg.getRecords()) {
                 String mimeType = new String(record.getType(), UTF_8);

                 if (MIME_TYPE_PROVISIONING_NFC.equals(mimeType)) {
                     return record;
                 }

                 // Assume only first record of message is used.
                 break;
             }
         }
         return null;
     }
 }
	/*
	* Copyright 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.managedprovisioning.parser;

	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_ADMIN_EXTRAS_BUNDLE;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_COMPONENT_NAME;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_MINIMUM_VERSION_CODE;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_CHECKSUM;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_DOWNLOAD_COOKIE_HEADER;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_DOWNLOAD_LOCATION;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_NAME;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_DEVICE_ADMIN_SIGNATURE_CHECKSUM;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_LEAVE_ALL_SYSTEM_APPS_ENABLED;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_LOCALE;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_LOCAL_TIME;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_SKIP_ENCRYPTION;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_TIME_ZONE;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_HIDDEN;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_PAC_URL;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_PASSWORD;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_PROXY_BYPASS;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_PROXY_HOST;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_PROXY_PORT;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_SECURITY_TYPE;
	import static android.app.admin.DevicePolicyManager.EXTRA_PROVISIONING_WIFI_SSID;
	import static android.app.admin.DevicePolicyManager.MIME_TYPE_PROVISIONING_NFC;
	import static android.nfc.NfcAdapter.ACTION_NDEF_DISCOVERED;
	import static com.android.internal.util.Preconditions.checkNotNull;
	import static java.nio.charset.StandardCharsets.UTF_8;

	import android.content.ComponentName;
	import android.content.Context;
	import android.content.Intent;
	import android.nfc.NdefMessage;
	import android.nfc.NdefRecord;
	import android.nfc.NfcAdapter;
	import android.os.Parcelable;
	import android.os.PersistableBundle;
	import android.support.annotation.Nullable;
	import android.support.annotation.VisibleForTesting;

	import com.android.managedprovisioning.ProvisionLogger;
	import com.android.managedprovisioning.common.IllegalProvisioningArgumentException;
	import com.android.managedprovisioning.common.Utils;
	import com.android.managedprovisioning.model.PackageDownloadInfo;
	import com.android.managedprovisioning.model.ProvisioningParams;
	import com.android.managedprovisioning.model.WifiInfo;

	import java.io.IOException;
	import java.io.StringReader;
	import java.util.Arrays;
	import java.util.Collections;
	import java.util.HashSet;
	import java.util.IllformedLocaleException;
	import java.util.Locale;
	import java.util.Properties;
	import java.util.Set;


	/**
	* A parser which parses provisioning data from intent which stores in {@link Properties}.
	*
	* <p>It is used to parse an intent contains the extra {@link NfcAdapter.EXTRA_NDEF_MESSAGES}, which
	* indicates that provisioning was started via Nfc bump. This extra contains an NDEF message, which
	* contains an NfcRecord with mime type {@link MIME_TYPE_PROVISIONING_NFC}. This record stores a
	* serialized properties object, which contains the serialized extras described in the next option.
	* A typical use case would be a programmer application that sends an Nfc bump to start Nfc
	* provisioning from a programmer device.
	*/
	@VisibleForTesting
	public class PropertiesProvisioningDataParser implements ProvisioningDataParser {

	private final Utils mUtils;

	PropertiesProvisioningDataParser(Utils utils) {
	mUtils = checkNotNull(utils);
	}

	public ProvisioningParams parse(Intent nfcIntent, Context context)
	throws IllegalProvisioningArgumentException {
	if (!ACTION_NDEF_DISCOVERED.equals(nfcIntent.getAction())) {
	throw new IllegalProvisioningArgumentException(
	"Only NFC action is supported in this parser.");
	}

	ProvisionLogger.logi("Processing Nfc Payload.");
	NdefRecord firstRecord = getFirstNdefRecord(nfcIntent);
	if (firstRecord != null) {
	try {
	Properties props = new Properties();
	props.load(new StringReader(new String(firstRecord.getPayload(), UTF_8)));

	// For parsing non-string parameters.
	String s = null;

	ProvisioningParams.Builder builder = ProvisioningParams.Builder.builder()
	.setStartedByTrustedSource(true)
	.setProvisioningAction(mUtils.mapIntentToDpmAction(nfcIntent))
	.setDeviceAdminPackageName(props.getProperty(
	EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_NAME));
	if ((s = props.getProperty(EXTRA_PROVISIONING_DEVICE_ADMIN_COMPONENT_NAME))
	!= null) {
	builder.setDeviceAdminComponentName(ComponentName.unflattenFromString(s));
	}

	// Parse time zone, locale and local time.
	builder.setTimeZone(props.getProperty(EXTRA_PROVISIONING_TIME_ZONE))
	.setLocale(MessageParser.stringToLocale(
	props.getProperty(EXTRA_PROVISIONING_LOCALE)));
	if ((s = props.getProperty(EXTRA_PROVISIONING_LOCAL_TIME)) != null) {
	builder.setLocalTime(Long.parseLong(s));
	}

	// Parse WiFi configuration.
	builder.setWifiInfo(parseWifiInfoFromProperties(props))
	// Parse device admin package download info.
	.setDeviceAdminDownloadInfo(parsePackageDownloadInfoFromProperties(props))
	// Parse EMM customized key-value pairs.
	// Note: EXTRA_PROVISIONING_ADMIN_EXTRAS_BUNDLE property contains a
	// Properties object serialized into String. See Properties.store() and
	// Properties.load() for more details. The property value is optional.
	.setAdminExtrasBundle(deserializeExtrasBundle(props,
	EXTRA_PROVISIONING_ADMIN_EXTRAS_BUNDLE));
	if ((s = props.getProperty(EXTRA_PROVISIONING_LEAVE_ALL_SYSTEM_APPS_ENABLED))
	!= null) {
	builder.setLeaveAllSystemAppsEnabled(Boolean.parseBoolean(s));
	}
	if ((s = props.getProperty(EXTRA_PROVISIONING_SKIP_ENCRYPTION)) != null) {
	builder.setSkipEncryption(Boolean.parseBoolean(s));
	}
	ProvisionLogger.logi("End processing Nfc Payload.");
	return builder.build();
	} catch (IOException e) {
	throw new IllegalProvisioningArgumentException("Couldn't load payload", e);
	} catch (NumberFormatException e) {
	throw new IllegalProvisioningArgumentException("Incorrect numberformat.", e);
	} catch (IllformedLocaleException e) {
	throw new IllegalProvisioningArgumentException("Invalid locale.", e);
	} catch (IllegalArgumentException e) {
	throw new IllegalProvisioningArgumentException("Invalid parameter found!", e);
	} catch (NullPointerException e) {
	throw new IllegalProvisioningArgumentException(
	"Compulsory parameter not found!", e);
	}
	}
	throw new IllegalProvisioningArgumentException(
	"Intent does not contain NfcRecord with the correct MIME type.");
	}

	/**
	* Parses Wifi configuration from an {@link Properties} and returns the result in
	* {@link WifiInfo}.
	*/
	@Nullable
	private WifiInfo parseWifiInfoFromProperties(Properties props) {
	if (props.getProperty(EXTRA_PROVISIONING_WIFI_SSID) == null) {
	return null;
	}
	WifiInfo.Builder builder = WifiInfo.Builder.builder()
	.setSsid(props.getProperty(EXTRA_PROVISIONING_WIFI_SSID))
	.setSecurityType(props.getProperty(EXTRA_PROVISIONING_WIFI_SECURITY_TYPE))
	.setPassword(props.getProperty(EXTRA_PROVISIONING_WIFI_PASSWORD))
	.setProxyHost(props.getProperty(EXTRA_PROVISIONING_WIFI_PROXY_HOST))
	.setProxyBypassHosts(props.getProperty(EXTRA_PROVISIONING_WIFI_PROXY_BYPASS))
	.setPacUrl(props.getProperty(EXTRA_PROVISIONING_WIFI_PAC_URL));
	// For parsing non-string parameters.
	String s = null;
	if ((s = props.getProperty(EXTRA_PROVISIONING_WIFI_PROXY_PORT)) != null) {
	builder.setProxyPort(Integer.parseInt(s));
	}
	if ((s = props.getProperty(EXTRA_PROVISIONING_WIFI_HIDDEN)) != null) {
	builder.setHidden(Boolean.parseBoolean(s));
	}

	return builder.build();
	}

	/**
	* Parses device admin package download info from an {@link Properties} and returns the result
	* in {@link PackageDownloadInfo}.
	*/
	@Nullable
	private PackageDownloadInfo parsePackageDownloadInfoFromProperties(Properties props) {
	if (props.getProperty(EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_DOWNLOAD_LOCATION) == null) {
	return null;
	}
	PackageDownloadInfo.Builder builder = PackageDownloadInfo.Builder.builder()
	.setLocation(props.getProperty(
	EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_DOWNLOAD_LOCATION))
	.setCookieHeader(props.getProperty(
	EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_DOWNLOAD_COOKIE_HEADER));
	// For parsing non-string parameters.
	String s = null;
	if ((s = props.getProperty(EXTRA_PROVISIONING_DEVICE_ADMIN_MINIMUM_VERSION_CODE)) != null) {
	builder.setMinVersion(Integer.parseInt(s));
	}
	if ((s = props.getProperty(EXTRA_PROVISIONING_DEVICE_ADMIN_PACKAGE_CHECKSUM)) != null) {
	// Still support SHA-1 for device admin package hash if we are provisioned by a Nfc
	// programmer.
	// TODO: remove once SHA-1 is fully deprecated.
	builder.setPackageChecksum(mUtils.stringToByteArray(s))
	.setPackageChecksumSupportsSha1(true);
	}
	if ((s = props.getProperty(EXTRA_PROVISIONING_DEVICE_ADMIN_SIGNATURE_CHECKSUM))
	!= null) {
	builder.setSignatureChecksum(mUtils.stringToByteArray(s));
	}
	return builder.build();
	}

	/**
	* Get a {@link PersistableBundle} from a String property in a Properties object.
	* @param props the source of the extra
	* @param extraName key into the Properties object
	* @return the bundle or {@code null} if there was no property with the given name
	* @throws IOException if there was an error parsing the propery
	*/
	private PersistableBundle deserializeExtrasBundle(Properties props, String extraName)
	throws IOException {
	PersistableBundle extrasBundle = null;
	String serializedExtras = props.getProperty(extraName);
	if (serializedExtras != null) {
	Properties extrasProp = new Properties();
	extrasProp.load(new StringReader(serializedExtras));
	extrasBundle = new PersistableBundle(extrasProp.size());
	for (String propName : extrasProp.stringPropertyNames()) {
	extrasBundle.putString(propName, extrasProp.getProperty(propName));
	}
	}
	return extrasBundle;
	}

	/**
	* @return the first {@link NdefRecord} found with a recognized MIME-type
	*/
	private NdefRecord getFirstNdefRecord(Intent nfcIntent) {
	// Only one first message with NFC_MIME_TYPE is used.
	for (Parcelable rawMsg : nfcIntent.getParcelableArrayExtra(
	NfcAdapter.EXTRA_NDEF_MESSAGES)) {
	NdefMessage msg = (NdefMessage) rawMsg;
	for (NdefRecord record : msg.getRecords()) {
	String mimeType = new String(record.getType(), UTF_8);

	if (MIME_TYPE_PROVISIONING_NFC.equals(mimeType)) {
	return record;
	}

	// Assume only first record of message is used.
	break;
	}
	}
	return null;
	}
	}