1/* 2 * [The "BSD licence"] 3 * Copyright (c) 2010 Ben Gruver (JesusFreke) 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. The name of the author may not be used to endorse or promote products 15 * derived from this software without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29package org.jf.dexlib; 30 31import org.jf.dexlib.Util.AnnotatedOutput; 32import org.jf.dexlib.Util.Input; 33import org.jf.dexlib.Util.Utf8Utils; 34 35public class HeaderItem extends Item<HeaderItem> { 36 /** 37 * the file format magic number, represented as the 38 * low-order bytes of a string 39 */ 40 public static final byte[] MAGIC = new byte[] {0x64, 0x65, 0x78, 0x0A, 0x30, 0x33, 0x35, 0x00};//"dex\n035" + '\0'; 41 42 43 /** size of this section, in bytes */ 44 private static final int HEADER_SIZE = 0x70; 45 46 /** the endianness constants */ 47 private static final int LITTLE_ENDIAN = 0x12345678; 48 private static final int BIG_ENDIAN = 0x78562312; 49 50 /** 51 * Create a new uninitialized <code>HeaderItem</code> 52 * @param dexFile The <code>DexFile</code> containing this <code>HeaderItem</code> 53 */ 54 protected HeaderItem(final DexFile dexFile) { 55 super(dexFile); 56 } 57 58 /** {@inheritDoc} */ 59 protected void readItem(Input in, ReadContext readContext) { 60 byte[] readMagic = in.readBytes(8); 61 62 for (int i=0; i<8; i++) { 63 if (MAGIC[i] != readMagic[i]) { 64 throw new RuntimeException("The magic value is not the expected value"); 65 } 66 } 67 68 in.readBytes(20); //checksum 69 in.readInt(); //signature 70 in.readInt(); //filesize 71 if (in.readInt() != HEADER_SIZE) { 72 throw new RuntimeException("The header size is not the expected value (0x70)"); 73 } 74 75 int endianTag = in.readInt(); 76 if (endianTag == BIG_ENDIAN) { 77 throw new RuntimeException("This dex file is big endian. Only little endian is currently supported."); 78 } else if (endianTag != LITTLE_ENDIAN) { 79 throw new RuntimeException("The endian tag is not 0x12345678 or 0x78563412"); 80 } 81 82 //link_size + link_off 83 if ((in.readInt() | in.readInt()) != 0) { 84 System.err.println("This dex file has a link section, which is not supported. Ignoring."); 85 } 86 87 int sectionSize; 88 int sectionOffset; 89 90 //map_offset 91 sectionOffset = in.readInt(); 92 readContext.addSection(ItemType.TYPE_MAP_LIST, 1, sectionOffset); 93 94 //string_id_item 95 sectionSize = in.readInt(); 96 sectionOffset = in.readInt(); 97 readContext.addSection(ItemType.TYPE_STRING_ID_ITEM, sectionSize, sectionOffset); 98 99 //type_id_item 100 sectionSize = in.readInt(); 101 sectionOffset = in.readInt(); 102 readContext.addSection(ItemType.TYPE_TYPE_ID_ITEM, sectionSize, sectionOffset); 103 104 //proto_id_item 105 sectionSize = in.readInt(); 106 sectionOffset = in.readInt(); 107 readContext.addSection(ItemType.TYPE_PROTO_ID_ITEM, sectionSize, sectionOffset); 108 109 //field_id_item 110 sectionSize = in.readInt(); 111 sectionOffset = in.readInt(); 112 readContext.addSection(ItemType.TYPE_FIELD_ID_ITEM, sectionSize, sectionOffset); 113 114 //method_id_item 115 sectionSize = in.readInt(); 116 sectionOffset = in.readInt(); 117 readContext.addSection(ItemType.TYPE_METHOD_ID_ITEM, sectionSize, sectionOffset); 118 119 //class_data_item 120 sectionSize = in.readInt(); 121 sectionOffset = in.readInt(); 122 readContext.addSection(ItemType.TYPE_CLASS_DEF_ITEM, sectionSize, sectionOffset); 123 124 in.readInt(); //data_size 125 in.readInt(); //data_off 126 } 127 128 /** {@inheritDoc} */ 129 protected int placeItem(int offset) { 130 return HEADER_SIZE; 131 } 132 133 /** {@inheritDoc} */ 134 protected void writeItem(AnnotatedOutput out) { 135 StringBuilder magicBuilder = new StringBuilder(); 136 for (int i=0; i<8; i++) { 137 magicBuilder.append((char)MAGIC[i]); 138 } 139 140 out.annotate("magic: " + Utf8Utils.escapeString(magicBuilder.toString())); 141 out.write(MAGIC); 142 143 out.annotate("checksum"); 144 out.writeInt(0); 145 146 out.annotate("signature"); 147 out.write(new byte[20]); 148 149 out.annotate("file_size: 0x" + Integer.toHexString(dexFile.getFileSize()) + " (" + dexFile.getFileSize() + 150 " bytes)"); 151 out.writeInt(dexFile.getFileSize()); 152 153 out.annotate("header_size: 0x" + Integer.toHexString(HEADER_SIZE)); 154 out.writeInt(HEADER_SIZE); 155 156 out.annotate("endian_tag: 0x" + Integer.toHexString(LITTLE_ENDIAN)); 157 out.writeInt(LITTLE_ENDIAN); 158 159 out.annotate("link_size: 0"); 160 out.writeInt(0); 161 162 out.annotate("link_off: 0"); 163 out.writeInt(0); 164 165 out.annotate("map_off: 0x" + Integer.toHexString(dexFile.MapItem.getOffset())); 166 out.writeInt(dexFile.MapItem.getOffset()); 167 168 out.annotate("string_ids_size: " + dexFile.StringIdsSection.getItems().size()); 169 out.writeInt(dexFile.StringIdsSection.getItems().size()); 170 171 out.annotate("string_ids_off: 0x" + Integer.toHexString(dexFile.StringIdsSection.getOffset())); 172 out.writeInt(dexFile.StringIdsSection.getOffset()); 173 174 out.annotate("type_ids_size: " + dexFile.TypeIdsSection.getItems().size()); 175 out.writeInt(dexFile.TypeIdsSection.getItems().size()); 176 177 out.annotate("type_ids_off: 0x" + Integer.toHexString(dexFile.TypeIdsSection.getOffset())); 178 out.writeInt(dexFile.TypeIdsSection.getOffset()); 179 180 out.annotate("proto_ids_size: " + dexFile.ProtoIdsSection.getItems().size()); 181 out.writeInt(dexFile.ProtoIdsSection.getItems().size()); 182 183 out.annotate("proto_ids_off: 0x" + Integer.toHexString(dexFile.ProtoIdsSection.getOffset())); 184 out.writeInt(dexFile.ProtoIdsSection.getOffset()); 185 186 out.annotate("field_ids_size: " + dexFile.FieldIdsSection.getItems().size()); 187 out.writeInt(dexFile.FieldIdsSection.getItems().size()); 188 189 out.annotate("field_ids_off: 0x" + Integer.toHexString(dexFile.FieldIdsSection.getOffset())); 190 out.writeInt(dexFile.FieldIdsSection.getOffset()); 191 192 out.annotate("method_ids_size: " + dexFile.MethodIdsSection.getItems().size()); 193 out.writeInt(dexFile.MethodIdsSection.getItems().size()); 194 195 out.annotate("method_ids_off: 0x" + Integer.toHexString(dexFile.MethodIdsSection.getOffset())); 196 out.writeInt(dexFile.MethodIdsSection.getOffset()); 197 198 out.annotate("class_defs_size: " + dexFile.ClassDefsSection.getItems().size()); 199 out.writeInt(dexFile.ClassDefsSection.getItems().size()); 200 201 out.annotate("class_defs_off: 0x" + Integer.toHexString(dexFile.ClassDefsSection.getOffset())); 202 out.writeInt(dexFile.ClassDefsSection.getOffset()); 203 204 out.annotate("data_size: 0x" + Integer.toHexString(dexFile.getDataSize()) + " (" + dexFile.getDataSize() + 205 " bytes)"); 206 out.writeInt(dexFile.getDataSize()); 207 208 out.annotate("data_off: 0x" + Integer.toHexString(dexFile.getDataOffset())); 209 out.writeInt(dexFile.getDataOffset()); 210 } 211 212 /** {@inheritDoc} */ 213 public ItemType getItemType() { 214 return ItemType.TYPE_HEADER_ITEM; 215 } 216 217 /** {@inheritDoc} */ 218 public String getConciseIdentity() { 219 return "header_item"; 220 } 221 222 /** {@inheritDoc} */ 223 public int compareTo(HeaderItem o) { 224 //there is only 1 header item 225 return 0; 226 } 227} 228