1 /* 2 * Copyright (C) 2008 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 17 #include "zip_archive.h" 18 19 #include <fcntl.h> 20 #include <stdio.h> 21 #include <sys/mman.h> // For the PROT_* and MAP_* constants. 22 #include <sys/stat.h> 23 #include <sys/types.h> 24 #include <unistd.h> 25 #include <vector> 26 27 #include "android-base/stringprintf.h" 28 #include "ziparchive/zip_archive.h" 29 30 #include "base/bit_utils.h" 31 #include "base/unix_file/fd_file.h" 32 #include "dex/dex_file.h" 33 34 namespace art { 35 36 // Log file contents and mmap info when mapping entries directly. 37 static constexpr const bool kDebugZipMapDirectly = false; 38 39 using android::base::StringPrintf; 40 41 uint32_t ZipEntry::GetUncompressedLength() { 42 return zip_entry_->uncompressed_length; 43 } 44 45 uint32_t ZipEntry::GetCrc32() { 46 return zip_entry_->crc32; 47 } 48 49 bool ZipEntry::IsUncompressed() { 50 return zip_entry_->method == kCompressStored; 51 } 52 53 bool ZipEntry::IsAlignedTo(size_t alignment) const { 54 DCHECK(IsPowerOfTwo(alignment)) << alignment; 55 return IsAlignedParam(zip_entry_->offset, static_cast<int>(alignment)); 56 } 57 58 bool ZipEntry::IsAlignedToDexHeader() const { 59 return IsAlignedTo(alignof(DexFile::Header)); 60 } 61 62 ZipEntry::~ZipEntry() { 63 delete zip_entry_; 64 } 65 66 bool ZipEntry::ExtractToFile(File& file, std::string* error_msg) { 67 const int32_t error = ExtractEntryToFile(handle_, zip_entry_, file.Fd()); 68 if (error) { 69 *error_msg = std::string(ErrorCodeString(error)); 70 return false; 71 } 72 73 return true; 74 } 75 76 MemMap* ZipEntry::ExtractToMemMap(const char* zip_filename, const char* entry_filename, 77 std::string* error_msg) { 78 std::string name(entry_filename); 79 name += " extracted in memory from "; 80 name += zip_filename; 81 std::unique_ptr<MemMap> map(MemMap::MapAnonymous(name.c_str(), 82 nullptr, GetUncompressedLength(), 83 PROT_READ | PROT_WRITE, false, false, 84 error_msg)); 85 if (map.get() == nullptr) { 86 DCHECK(!error_msg->empty()); 87 return nullptr; 88 } 89 90 const int32_t error = ExtractToMemory(handle_, zip_entry_, 91 map->Begin(), map->Size()); 92 if (error) { 93 *error_msg = std::string(ErrorCodeString(error)); 94 return nullptr; 95 } 96 97 return map.release(); 98 } 99 100 MemMap* ZipEntry::MapDirectlyFromFile(const char* zip_filename, std::string* error_msg) { 101 const int zip_fd = GetFileDescriptor(handle_); 102 const char* entry_filename = entry_name_.c_str(); 103 104 // Should not happen since we don't have a memory ZipArchive constructor. 105 // However the underlying ZipArchive isn't required to have an FD, 106 // so check to be sure. 107 CHECK_GE(zip_fd, 0) << 108 StringPrintf("Cannot map '%s' (in zip '%s') directly because the zip archive " 109 "is not file backed.", 110 entry_filename, 111 zip_filename); 112 113 if (!IsUncompressed()) { 114 *error_msg = StringPrintf("Cannot map '%s' (in zip '%s') directly because it is compressed.", 115 entry_filename, 116 zip_filename); 117 return nullptr; 118 } else if (zip_entry_->uncompressed_length != zip_entry_->compressed_length) { 119 *error_msg = StringPrintf("Cannot map '%s' (in zip '%s') directly because " 120 "entry has bad size (%u != %u).", 121 entry_filename, 122 zip_filename, 123 zip_entry_->uncompressed_length, 124 zip_entry_->compressed_length); 125 return nullptr; 126 } 127 128 std::string name(entry_filename); 129 name += " mapped directly in memory from "; 130 name += zip_filename; 131 132 const off_t offset = zip_entry_->offset; 133 134 if (kDebugZipMapDirectly) { 135 LOG(INFO) << "zip_archive: " << "make mmap of " << name << " @ offset = " << offset; 136 } 137 138 std::unique_ptr<MemMap> map( 139 MemMap::MapFileAtAddress(nullptr, // Expected pointer address 140 GetUncompressedLength(), // Byte count 141 PROT_READ | PROT_WRITE, 142 MAP_PRIVATE, 143 zip_fd, 144 offset, 145 false, // Don't restrict allocation to lower4GB 146 false, // Doesn't overlap existing map (reuse=false) 147 name.c_str(), 148 /*out*/error_msg)); 149 150 if (map == nullptr) { 151 DCHECK(!error_msg->empty()); 152 } 153 154 if (kDebugZipMapDirectly) { 155 // Dump contents of file, same format as using this shell command: 156 // $> od -j <offset> -t x1 <zip_filename> 157 static constexpr const int kMaxDumpChars = 15; 158 lseek(zip_fd, 0, SEEK_SET); 159 160 int count = offset + kMaxDumpChars; 161 162 std::string tmp; 163 char buf; 164 165 // Dump file contents. 166 int i = 0; 167 while (read(zip_fd, &buf, 1) > 0 && i < count) { 168 tmp += StringPrintf("%3d ", (unsigned int)buf); 169 ++i; 170 } 171 172 LOG(INFO) << "map_fd raw bytes starting at 0"; 173 LOG(INFO) << "" << tmp; 174 LOG(INFO) << "---------------------------"; 175 176 // Dump map contents. 177 if (map != nullptr) { 178 tmp = ""; 179 180 count = kMaxDumpChars; 181 182 uint8_t* begin = map->Begin(); 183 for (i = 0; i < count; ++i) { 184 tmp += StringPrintf("%3d ", (unsigned int)begin[i]); 185 } 186 187 LOG(INFO) << "map address " << StringPrintf("%p", begin); 188 LOG(INFO) << "map first " << kMaxDumpChars << " chars:"; 189 LOG(INFO) << tmp; 190 } 191 } 192 193 return map.release(); 194 } 195 196 MemMap* ZipEntry::MapDirectlyOrExtract(const char* zip_filename, 197 const char* entry_filename, 198 std::string* error_msg) { 199 if (IsUncompressed() && GetFileDescriptor(handle_) >= 0) { 200 MemMap* ret = MapDirectlyFromFile(zip_filename, error_msg); 201 if (ret != nullptr) { 202 return ret; 203 } 204 } 205 // Fall back to extraction for the failure case. 206 return ExtractToMemMap(zip_filename, entry_filename, error_msg); 207 } 208 209 static void SetCloseOnExec(int fd) { 210 // This dance is more portable than Linux's O_CLOEXEC open(2) flag. 211 int flags = fcntl(fd, F_GETFD); 212 if (flags == -1) { 213 PLOG(WARNING) << "fcntl(" << fd << ", F_GETFD) failed"; 214 return; 215 } 216 int rc = fcntl(fd, F_SETFD, flags | FD_CLOEXEC); 217 if (rc == -1) { 218 PLOG(WARNING) << "fcntl(" << fd << ", F_SETFD, " << flags << ") failed"; 219 return; 220 } 221 } 222 223 ZipArchive* ZipArchive::Open(const char* filename, std::string* error_msg) { 224 DCHECK(filename != nullptr); 225 226 ZipArchiveHandle handle; 227 const int32_t error = OpenArchive(filename, &handle); 228 if (error) { 229 *error_msg = std::string(ErrorCodeString(error)); 230 CloseArchive(handle); 231 return nullptr; 232 } 233 234 SetCloseOnExec(GetFileDescriptor(handle)); 235 return new ZipArchive(handle); 236 } 237 238 ZipArchive* ZipArchive::OpenFromFd(int fd, const char* filename, std::string* error_msg) { 239 DCHECK(filename != nullptr); 240 DCHECK_GT(fd, 0); 241 242 ZipArchiveHandle handle; 243 const int32_t error = OpenArchiveFd(fd, filename, &handle); 244 if (error) { 245 *error_msg = std::string(ErrorCodeString(error)); 246 CloseArchive(handle); 247 return nullptr; 248 } 249 250 SetCloseOnExec(GetFileDescriptor(handle)); 251 return new ZipArchive(handle); 252 } 253 254 ZipEntry* ZipArchive::Find(const char* name, std::string* error_msg) const { 255 DCHECK(name != nullptr); 256 257 // Resist the urge to delete the space. <: is a bigraph sequence. 258 std::unique_ptr< ::ZipEntry> zip_entry(new ::ZipEntry); 259 const int32_t error = FindEntry(handle_, ZipString(name), zip_entry.get()); 260 if (error) { 261 *error_msg = std::string(ErrorCodeString(error)); 262 return nullptr; 263 } 264 265 return new ZipEntry(handle_, zip_entry.release(), name); 266 } 267 268 ZipArchive::~ZipArchive() { 269 CloseArchive(handle_); 270 } 271 272 } // namespace art 273
