1 /* 2 * Copyright (C) 2015 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package libcore.tzdata.update; 17 18 import java.io.ByteArrayInputStream; 19 import java.io.File; 20 import java.io.FileOutputStream; 21 import java.io.IOException; 22 import java.io.InputStream; 23 import java.util.Arrays; 24 import java.util.zip.ZipEntry; 25 import java.util.zip.ZipInputStream; 26 27 /** 28 * A configuration bundle. This is a thin wrapper around some in-memory bytes representing a zip 29 * archive and logic for its safe extraction. 30 */ 31 public final class ConfigBundle { 32 33 /** The name of the file inside the bundle containing the TZ data version. */ 34 public static final String TZ_DATA_VERSION_FILE_NAME = "tzdata_version"; 35 36 /** The name of the file inside the bundle containing the expected device checksums. */ 37 public static final String CHECKSUMS_FILE_NAME = "checksums"; 38 39 /** The name of the file inside the bundle containing bionic/libcore TZ data. */ 40 public static final String ZONEINFO_FILE_NAME = "tzdata"; 41 42 /** The name of the file inside the bundle containing ICU TZ data. */ 43 public static final String ICU_DATA_FILE_NAME = "icu/icu_tzdata.dat"; 44 45 private static final int BUFFER_SIZE = 8192; 46 47 private final byte[] bytes; 48 ConfigBundle(byte[] bytes)49 public ConfigBundle(byte[] bytes) { 50 this.bytes = bytes; 51 } 52 getBundleBytes()53 public byte[] getBundleBytes() { 54 return bytes; 55 } 56 extractTo(File targetDir)57 public void extractTo(File targetDir) throws IOException { 58 extractZipSafely(new ByteArrayInputStream(bytes), targetDir, true /* makeWorldReadable */); 59 } 60 61 /** Visible for testing */ extractZipSafely(InputStream is, File targetDir, boolean makeWorldReadable)62 static void extractZipSafely(InputStream is, File targetDir, boolean makeWorldReadable) 63 throws IOException { 64 65 // Create the extraction dir, if needed. 66 FileUtils.ensureDirectoriesExist(targetDir, makeWorldReadable); 67 68 try (ZipInputStream zipInputStream = new ZipInputStream(is)) { 69 byte[] buffer = new byte[BUFFER_SIZE]; 70 ZipEntry entry; 71 while ((entry = zipInputStream.getNextEntry()) != null) { 72 // Validate the entry name: make sure the unpacked file will exist beneath the 73 // targetDir. 74 String name = entry.getName(); 75 // Note, we assume that nothing will quickly insert a symlink after createSubFile() 76 // that might invalidate the guarantees about name existing beneath targetDir. 77 File entryFile = FileUtils.createSubFile(targetDir, name); 78 79 if (entry.isDirectory()) { 80 FileUtils.ensureDirectoriesExist(entryFile, makeWorldReadable); 81 } else { 82 // Create the path if there was no directory entry. 83 if (!entryFile.getParentFile().exists()) { 84 FileUtils.ensureDirectoriesExist( 85 entryFile.getParentFile(), makeWorldReadable); 86 } 87 88 try (FileOutputStream fos = new FileOutputStream(entryFile)) { 89 int count; 90 while ((count = zipInputStream.read(buffer)) != -1) { 91 fos.write(buffer, 0, count); 92 } 93 // sync to disk 94 fos.getFD().sync(); 95 } 96 // mark entryFile -rw-r--r-- 97 if (makeWorldReadable) { 98 FileUtils.makeWorldReadable(entryFile); 99 } 100 } 101 } 102 } 103 } 104 105 @Override equals(Object o)106 public boolean equals(Object o) { 107 if (this == o) { 108 return true; 109 } 110 if (o == null || getClass() != o.getClass()) { 111 return false; 112 } 113 114 ConfigBundle that = (ConfigBundle) o; 115 116 if (!Arrays.equals(bytes, that.bytes)) { 117 return false; 118 } 119 120 return true; 121 } 122 123 } 124