tzdata/update2/src/main/libcore/tzdata/update2/TimeZoneDistroInstaller.java - platform/libcore - Git at Google

 /*
  * Copyright (C) 2015 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 libcore.tzdata.update2;

 import android.util.Slog;

 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
 import libcore.tzdata.shared2.DistroException;
 import libcore.tzdata.shared2.DistroVersion;
 import libcore.tzdata.shared2.FileUtils;
 import libcore.tzdata.shared2.TimeZoneDistro;
 import libcore.util.ZoneInfoDB;

 /**
  * A distro-validation / extraction class. Separate from the services code that uses it for easier
  * testing. This class is not thread-safe: callers are expected to handle mutual exclusion.
  */
 public final class TimeZoneDistroInstaller {
     /** {@link #installWithErrorCode(byte[])} result code: Success. */
     public final static int INSTALL_SUCCESS = 0;
     /** {@link #installWithErrorCode(byte[])} result code: Distro corrupt. */
     public final static int INSTALL_FAIL_BAD_DISTRO_STRUCTURE = 1;
     /** {@link #installWithErrorCode(byte[])} result code: Distro version incompatible. */
     public final static int INSTALL_FAIL_BAD_DISTRO_FORMAT_VERSION = 2;
     /** {@link #installWithErrorCode(byte[])} result code: Distro rules too old for device. */
     public final static int INSTALL_FAIL_RULES_TOO_OLD = 3;
     /** {@link #installWithErrorCode(byte[])} result code: Distro content failed validation. */
     public final static int INSTALL_FAIL_VALIDATION_ERROR = 4;

     private static final String CURRENT_TZ_DATA_DIR_NAME = "current";
     private static final String WORKING_DIR_NAME = "working";
     private static final String OLD_TZ_DATA_DIR_NAME = "old";

     private final String logTag;
     private final File systemTzDataFile;
     private final File oldTzDataDir;
     private final File currentTzDataDir;
     private final File workingDir;

     public TimeZoneDistroInstaller(String logTag, File systemTzDataFile, File installDir) {
         this.logTag = logTag;
         this.systemTzDataFile = systemTzDataFile;
         oldTzDataDir = new File(installDir, OLD_TZ_DATA_DIR_NAME);
         currentTzDataDir = new File(installDir, CURRENT_TZ_DATA_DIR_NAME);
         workingDir = new File(installDir, WORKING_DIR_NAME);
     }

     // VisibleForTesting
     File getOldTzDataDir() {
         return oldTzDataDir;
     }

     // VisibleForTesting
     File getCurrentTzDataDir() {
         return currentTzDataDir;
     }

     // VisibleForTesting
     File getWorkingDir() {
         return workingDir;
     }

     /**
      * Install the supplied content.
      *
      * <p>Errors during unpacking or installation will throw an {@link IOException}.
      * If the distro content is invalid this method returns {@code false}.
      * If the installation completed successfully this method returns {@code true}.
      */
     public boolean install(byte[] content) throws IOException {
         int result = installWithErrorCode(content);
         return result == INSTALL_SUCCESS;
     }

     /**
      * Install the supplied time zone distro.
      *
      * <p>Errors during unpacking or installation will throw an {@link IOException}.
      * Returns {@link #INSTALL_SUCCESS} or an error code.
      */
     public int installWithErrorCode(byte[] content) throws IOException {
         if (oldTzDataDir.exists()) {
             FileUtils.deleteRecursive(oldTzDataDir);
         }
         if (workingDir.exists()) {
             FileUtils.deleteRecursive(workingDir);
         }

         Slog.i(logTag, "Unpacking / verifying time zone update");
         unpackDistro(content, workingDir);
         try {
             DistroVersion distroVersion;
             try {
                 distroVersion = readDistroVersion(workingDir);
             } catch (DistroException e) {
                 Slog.i(logTag, "Invalid distro version: " + e.getMessage());
                 return INSTALL_FAIL_BAD_DISTRO_STRUCTURE;
             }
             if (distroVersion == null) {
                 Slog.i(logTag, "Update not applied: Distro version could not be loaded");
                 return INSTALL_FAIL_BAD_DISTRO_STRUCTURE;
             }
             if (!DistroVersion.isCompatibleWithThisDevice(distroVersion)) {
                 Slog.i(logTag, "Update not applied: Distro format version check failed: "
                         + distroVersion);
                 return INSTALL_FAIL_BAD_DISTRO_FORMAT_VERSION;
             }

             if (!checkDistroDataFilesExist(workingDir)) {
                 Slog.i(logTag, "Update not applied: Distro is missing required data file(s)");
                 return INSTALL_FAIL_BAD_DISTRO_STRUCTURE;
             }

             if (!checkDistroRulesNewerThanSystem(systemTzDataFile, distroVersion)) {
                 Slog.i(logTag, "Update not applied: Distro rules version check failed");
                 return INSTALL_FAIL_RULES_TOO_OLD;
             }

             File zoneInfoFile = new File(workingDir, TimeZoneDistro.TZDATA_FILE_NAME);
             ZoneInfoDB.TzData tzData = ZoneInfoDB.TzData.loadTzData(zoneInfoFile.getPath());
             if (tzData == null) {
                 Slog.i(logTag, "Update not applied: " + zoneInfoFile + " could not be loaded");
                 return INSTALL_FAIL_VALIDATION_ERROR;
             }
             try {
                 tzData.validate();
             } catch (IOException e) {
                 Slog.i(logTag, "Update not applied: " + zoneInfoFile + " failed validation", e);
                 return INSTALL_FAIL_VALIDATION_ERROR;
             } finally {
                 tzData.close();
             }
             // TODO(nfuller): Add deeper validity checks / canarying before applying.
             // http://b/31008728

             Slog.i(logTag, "Applying time zone update");
             FileUtils.makeDirectoryWorldAccessible(workingDir);

             if (currentTzDataDir.exists()) {
                 Slog.i(logTag, "Moving " + currentTzDataDir + " to " + oldTzDataDir);
                 FileUtils.rename(currentTzDataDir, oldTzDataDir);
             }
             Slog.i(logTag, "Moving " + workingDir + " to " + currentTzDataDir);
             FileUtils.rename(workingDir, currentTzDataDir);
             Slog.i(logTag, "Update applied: " + currentTzDataDir + " successfully created");
             return INSTALL_SUCCESS;
         } finally {
             deleteBestEffort(oldTzDataDir);
             deleteBestEffort(workingDir);
         }
     }

     /**
      * Uninstall the current timezone update in /data, returning the device to using data from
      * /system. Returns {@code true} if uninstallation was successful, {@code false} if there was
      * nothing installed in /data to uninstall.
      *
      * <p>Errors encountered during uninstallation will throw an {@link IOException}.
      */
     public boolean uninstall() throws IOException {
         Slog.i(logTag, "Uninstalling time zone update");

         // Make sure we don't have a dir where we're going to move the currently installed data to.
         if (oldTzDataDir.exists()) {
             // If we can't remove this, an exception is thrown and we don't continue.
             FileUtils.deleteRecursive(oldTzDataDir);
         }

         if (!currentTzDataDir.exists()) {
             Slog.i(logTag, "Nothing to uninstall at " + currentTzDataDir);
             return false;
         }

         Slog.i(logTag, "Moving " + currentTzDataDir + " to " + oldTzDataDir);
         // Move currentTzDataDir out of the way in one operation so we can't partially delete
         // the contents, which would leave a partial install.
         FileUtils.rename(currentTzDataDir, oldTzDataDir);

         // Do our best to delete the now uninstalled timezone data.
         deleteBestEffort(oldTzDataDir);

         Slog.i(logTag, "Time zone update uninstalled.");

         return true;
     }

     /**
      * Reads the currently installed distro version. Returns {@code null} if there is no distro
      * installed.
      *
      * @throws IOException if there was a problem reading data from /data
      * @throws DistroException if there was a problem with the installed distro format/structure
      */
     public DistroVersion getInstalledDistroVersion() throws DistroException, IOException {
         if (!currentTzDataDir.exists()) {
             return null;
         }
         return readDistroVersion(currentTzDataDir);
     }

     /**
      * Reads the timezone rules version present in /system. i.e. the version that would be present
      * after a factory reset.
      *
      * @throws IOException if there was a problem reading data
      */
     public String getSystemRulesVersion() throws IOException {
         return readSystemRulesVersion(systemTzDataFile);
     }

     private void deleteBestEffort(File dir) {
         if (dir.exists()) {
             Slog.i(logTag, "Deleting " + dir);
             try {
                 FileUtils.deleteRecursive(dir);
             } catch (IOException e) {
                 // Logged but otherwise ignored.
                 Slog.w(logTag, "Unable to delete " + dir, e);
             }
         }
     }

     private void unpackDistro(byte[] content, File targetDir) throws IOException {
         Slog.i(logTag, "Unpacking update content to: " + targetDir);
         TimeZoneDistro distro = new TimeZoneDistro(content);
         distro.extractTo(targetDir);
     }

     private boolean checkDistroDataFilesExist(File unpackedContentDir) throws IOException {
         Slog.i(logTag, "Verifying distro contents");
         return FileUtils.filesExist(unpackedContentDir,
                 TimeZoneDistro.TZDATA_FILE_NAME,
                 TimeZoneDistro.ICU_DATA_FILE_NAME);
     }

     private DistroVersion readDistroVersion(File distroDir) throws DistroException, IOException {
         Slog.i(logTag, "Reading distro format version");
         File distroVersionFile = new File(distroDir, TimeZoneDistro.DISTRO_VERSION_FILE_NAME);
         if (!distroVersionFile.exists()) {
             throw new DistroException("No distro version file found: " + distroVersionFile);
         }
         byte[] versionBytes =
                 FileUtils.readBytes(distroVersionFile, DistroVersion.DISTRO_VERSION_FILE_LENGTH);
         return DistroVersion.fromBytes(versionBytes);
     }

     /**
      * Returns true if the the distro IANA rules version is >= system IANA rules version.
      */
     private boolean checkDistroRulesNewerThanSystem(
             File systemTzDataFile, DistroVersion distroVersion) throws IOException {

         // We only check the /system tzdata file and assume that other data like ICU is in sync.
         // There is a CTS test that checks ICU and bionic/libcore are in sync.
         Slog.i(logTag, "Reading /system rules version");
         String systemRulesVersion = readSystemRulesVersion(systemTzDataFile);

         String distroRulesVersion = distroVersion.rulesVersion;
         // canApply = distroRulesVersion >= systemRulesVersion
         boolean canApply = distroRulesVersion.compareTo(systemRulesVersion) >= 0;
         if (!canApply) {
             Slog.i(logTag, "Failed rules version check: distroRulesVersion="
                     + distroRulesVersion + ", systemRulesVersion=" + systemRulesVersion);
         } else {
             Slog.i(logTag, "Passed rules version check: distroRulesVersion="
                     + distroRulesVersion + ", systemRulesVersion=" + systemRulesVersion);
         }
         return canApply;
     }

     private String readSystemRulesVersion(File systemTzDataFile) throws IOException {
         if (!systemTzDataFile.exists()) {
             Slog.i(logTag, "tzdata file cannot be found in /system");
             throw new FileNotFoundException("system tzdata does not exist: " + systemTzDataFile);
         }
         return ZoneInfoDB.TzData.getRulesVersion(systemTzDataFile);
     }
 }
	/*
	* Copyright (C) 2015 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 libcore.tzdata.update2;

	import android.util.Slog;

	import java.io.File;
	import java.io.FileNotFoundException;
	import java.io.IOException;
	import libcore.tzdata.shared2.DistroException;
	import libcore.tzdata.shared2.DistroVersion;
	import libcore.tzdata.shared2.FileUtils;
	import libcore.tzdata.shared2.TimeZoneDistro;
	import libcore.util.ZoneInfoDB;

	/**
	* A distro-validation / extraction class. Separate from the services code that uses it for easier
	* testing. This class is not thread-safe: callers are expected to handle mutual exclusion.
	*/
	public final class TimeZoneDistroInstaller {
	/** {@link #installWithErrorCode(byte[])} result code: Success. */
	public final static int INSTALL_SUCCESS = 0;
	/** {@link #installWithErrorCode(byte[])} result code: Distro corrupt. */
	public final static int INSTALL_FAIL_BAD_DISTRO_STRUCTURE = 1;
	/** {@link #installWithErrorCode(byte[])} result code: Distro version incompatible. */
	public final static int INSTALL_FAIL_BAD_DISTRO_FORMAT_VERSION = 2;
	/** {@link #installWithErrorCode(byte[])} result code: Distro rules too old for device. */
	public final static int INSTALL_FAIL_RULES_TOO_OLD = 3;
	/** {@link #installWithErrorCode(byte[])} result code: Distro content failed validation. */
	public final static int INSTALL_FAIL_VALIDATION_ERROR = 4;

	private static final String CURRENT_TZ_DATA_DIR_NAME = "current";
	private static final String WORKING_DIR_NAME = "working";
	private static final String OLD_TZ_DATA_DIR_NAME = "old";

	private final String logTag;
	private final File systemTzDataFile;
	private final File oldTzDataDir;
	private final File currentTzDataDir;
	private final File workingDir;

	public TimeZoneDistroInstaller(String logTag, File systemTzDataFile, File installDir) {
	this.logTag = logTag;
	this.systemTzDataFile = systemTzDataFile;
	oldTzDataDir = new File(installDir, OLD_TZ_DATA_DIR_NAME);
	currentTzDataDir = new File(installDir, CURRENT_TZ_DATA_DIR_NAME);
	workingDir = new File(installDir, WORKING_DIR_NAME);
	}

	// VisibleForTesting
	File getOldTzDataDir() {
	return oldTzDataDir;
	}

	// VisibleForTesting
	File getCurrentTzDataDir() {
	return currentTzDataDir;
	}

	// VisibleForTesting
	File getWorkingDir() {
	return workingDir;
	}

	/**
	* Install the supplied content.
	*
	* <p>Errors during unpacking or installation will throw an {@link IOException}.
	* If the distro content is invalid this method returns {@code false}.
	* If the installation completed successfully this method returns {@code true}.
	*/
	public boolean install(byte[] content) throws IOException {
	int result = installWithErrorCode(content);
	return result == INSTALL_SUCCESS;
	}

	/**
	* Install the supplied time zone distro.
	*
	* <p>Errors during unpacking or installation will throw an {@link IOException}.
	* Returns {@link #INSTALL_SUCCESS} or an error code.
	*/
	public int installWithErrorCode(byte[] content) throws IOException {
	if (oldTzDataDir.exists()) {
	FileUtils.deleteRecursive(oldTzDataDir);
	}
	if (workingDir.exists()) {
	FileUtils.deleteRecursive(workingDir);
	}

	Slog.i(logTag, "Unpacking / verifying time zone update");
	unpackDistro(content, workingDir);
	try {
	DistroVersion distroVersion;
	try {
	distroVersion = readDistroVersion(workingDir);
	} catch (DistroException e) {
	Slog.i(logTag, "Invalid distro version: " + e.getMessage());
	return INSTALL_FAIL_BAD_DISTRO_STRUCTURE;
	}
	if (distroVersion == null) {
	Slog.i(logTag, "Update not applied: Distro version could not be loaded");
	return INSTALL_FAIL_BAD_DISTRO_STRUCTURE;
	}
	if (!DistroVersion.isCompatibleWithThisDevice(distroVersion)) {
	Slog.i(logTag, "Update not applied: Distro format version check failed: "
	+ distroVersion);
	return INSTALL_FAIL_BAD_DISTRO_FORMAT_VERSION;
	}

	if (!checkDistroDataFilesExist(workingDir)) {
	Slog.i(logTag, "Update not applied: Distro is missing required data file(s)");
	return INSTALL_FAIL_BAD_DISTRO_STRUCTURE;
	}

	if (!checkDistroRulesNewerThanSystem(systemTzDataFile, distroVersion)) {
	Slog.i(logTag, "Update not applied: Distro rules version check failed");
	return INSTALL_FAIL_RULES_TOO_OLD;
	}

	File zoneInfoFile = new File(workingDir, TimeZoneDistro.TZDATA_FILE_NAME);
	ZoneInfoDB.TzData tzData = ZoneInfoDB.TzData.loadTzData(zoneInfoFile.getPath());
	if (tzData == null) {
	Slog.i(logTag, "Update not applied: " + zoneInfoFile + " could not be loaded");
	return INSTALL_FAIL_VALIDATION_ERROR;
	}
	try {
	tzData.validate();
	} catch (IOException e) {
	Slog.i(logTag, "Update not applied: " + zoneInfoFile + " failed validation", e);
	return INSTALL_FAIL_VALIDATION_ERROR;
	} finally {
	tzData.close();
	}
	// TODO(nfuller): Add deeper validity checks / canarying before applying.
	// http://b/31008728

	Slog.i(logTag, "Applying time zone update");
	FileUtils.makeDirectoryWorldAccessible(workingDir);

	if (currentTzDataDir.exists()) {
	Slog.i(logTag, "Moving " + currentTzDataDir + " to " + oldTzDataDir);
	FileUtils.rename(currentTzDataDir, oldTzDataDir);
	}
	Slog.i(logTag, "Moving " + workingDir + " to " + currentTzDataDir);
	FileUtils.rename(workingDir, currentTzDataDir);
	Slog.i(logTag, "Update applied: " + currentTzDataDir + " successfully created");
	return INSTALL_SUCCESS;
	} finally {
	deleteBestEffort(oldTzDataDir);
	deleteBestEffort(workingDir);
	}
	}

	/**
	* Uninstall the current timezone update in /data, returning the device to using data from
	* /system. Returns {@code true} if uninstallation was successful, {@code false} if there was
	* nothing installed in /data to uninstall.
	*
	* <p>Errors encountered during uninstallation will throw an {@link IOException}.
	*/
	public boolean uninstall() throws IOException {
	Slog.i(logTag, "Uninstalling time zone update");

	// Make sure we don't have a dir where we're going to move the currently installed data to.
	if (oldTzDataDir.exists()) {
	// If we can't remove this, an exception is thrown and we don't continue.
	FileUtils.deleteRecursive(oldTzDataDir);
	}

	if (!currentTzDataDir.exists()) {
	Slog.i(logTag, "Nothing to uninstall at " + currentTzDataDir);
	return false;
	}

	Slog.i(logTag, "Moving " + currentTzDataDir + " to " + oldTzDataDir);
	// Move currentTzDataDir out of the way in one operation so we can't partially delete
	// the contents, which would leave a partial install.
	FileUtils.rename(currentTzDataDir, oldTzDataDir);

	// Do our best to delete the now uninstalled timezone data.
	deleteBestEffort(oldTzDataDir);

	Slog.i(logTag, "Time zone update uninstalled.");

	return true;
	}

	/**
	* Reads the currently installed distro version. Returns {@code null} if there is no distro
	* installed.
	*
	* @throws IOException if there was a problem reading data from /data
	* @throws DistroException if there was a problem with the installed distro format/structure
	*/
	public DistroVersion getInstalledDistroVersion() throws DistroException, IOException {
	if (!currentTzDataDir.exists()) {
	return null;
	}
	return readDistroVersion(currentTzDataDir);
	}

	/**
	* Reads the timezone rules version present in /system. i.e. the version that would be present
	* after a factory reset.
	*
	* @throws IOException if there was a problem reading data
	*/
	public String getSystemRulesVersion() throws IOException {
	return readSystemRulesVersion(systemTzDataFile);
	}

	private void deleteBestEffort(File dir) {
	if (dir.exists()) {
	Slog.i(logTag, "Deleting " + dir);
	try {
	FileUtils.deleteRecursive(dir);
	} catch (IOException e) {
	// Logged but otherwise ignored.
	Slog.w(logTag, "Unable to delete " + dir, e);
	}
	}
	}

	private void unpackDistro(byte[] content, File targetDir) throws IOException {
	Slog.i(logTag, "Unpacking update content to: " + targetDir);
	TimeZoneDistro distro = new TimeZoneDistro(content);
	distro.extractTo(targetDir);
	}

	private boolean checkDistroDataFilesExist(File unpackedContentDir) throws IOException {
	Slog.i(logTag, "Verifying distro contents");
	return FileUtils.filesExist(unpackedContentDir,
	TimeZoneDistro.TZDATA_FILE_NAME,
	TimeZoneDistro.ICU_DATA_FILE_NAME);
	}

	private DistroVersion readDistroVersion(File distroDir) throws DistroException, IOException {
	Slog.i(logTag, "Reading distro format version");
	File distroVersionFile = new File(distroDir, TimeZoneDistro.DISTRO_VERSION_FILE_NAME);
	if (!distroVersionFile.exists()) {
	throw new DistroException("No distro version file found: " + distroVersionFile);
	}
	byte[] versionBytes =
	FileUtils.readBytes(distroVersionFile, DistroVersion.DISTRO_VERSION_FILE_LENGTH);
	return DistroVersion.fromBytes(versionBytes);
	}

	/**
	* Returns true if the the distro IANA rules version is >= system IANA rules version.
	*/
	private boolean checkDistroRulesNewerThanSystem(
	File systemTzDataFile, DistroVersion distroVersion) throws IOException {

	// We only check the /system tzdata file and assume that other data like ICU is in sync.
	// There is a CTS test that checks ICU and bionic/libcore are in sync.
	Slog.i(logTag, "Reading /system rules version");
	String systemRulesVersion = readSystemRulesVersion(systemTzDataFile);

	String distroRulesVersion = distroVersion.rulesVersion;
	// canApply = distroRulesVersion >= systemRulesVersion
	boolean canApply = distroRulesVersion.compareTo(systemRulesVersion) >= 0;
	if (!canApply) {
	Slog.i(logTag, "Failed rules version check: distroRulesVersion="
	+ distroRulesVersion + ", systemRulesVersion=" + systemRulesVersion);
	} else {
	Slog.i(logTag, "Passed rules version check: distroRulesVersion="
	+ distroRulesVersion + ", systemRulesVersion=" + systemRulesVersion);
	}
	return canApply;
	}

	private String readSystemRulesVersion(File systemTzDataFile) throws IOException {
	if (!systemTzDataFile.exists()) {
	Slog.i(logTag, "tzdata file cannot be found in /system");
	throw new FileNotFoundException("system tzdata does not exist: " + systemTzDataFile);
	}
	return ZoneInfoDB.TzData.getRulesVersion(systemTzDataFile);
	}
	}