| /* |
| * Copyright (C) 2017 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. |
| */ |
| |
| #include "dex_file_loader.h" |
| |
| #include <sys/mman.h> // For the PROT_* and MAP_* constants. |
| #include <sys/stat.h> |
| |
| #include "android-base/stringprintf.h" |
| |
| #include "base/file_magic.h" |
| #include "base/stl_util.h" |
| #include "base/systrace.h" |
| #include "base/unix_file/fd_file.h" |
| #include "dex_file.h" |
| #include "dex_file_verifier.h" |
| #include "native_dex_file.h" |
| #include "zip_archive.h" |
| |
| namespace art { |
| |
| using android::base::StringPrintf; |
| |
| static constexpr OatDexFile* kNoOatDexFile = nullptr; |
| |
| |
| bool DexFileLoader::IsValidMagic(uint32_t magic) { |
| return IsValidMagic(reinterpret_cast<uint8_t*>(&magic)); |
| } |
| |
| bool DexFileLoader::IsValidMagic(const uint8_t* magic) { |
| return NativeDexFile::IsMagicValid(magic); |
| } |
| |
| bool DexFileLoader::GetMultiDexChecksums(const char* filename, |
| std::vector<uint32_t>* checksums, |
| std::string* error_msg) { |
| CHECK(checksums != nullptr); |
| uint32_t magic; |
| |
| File fd = OpenAndReadMagic(filename, &magic, error_msg); |
| if (fd.Fd() == -1) { |
| DCHECK(!error_msg->empty()); |
| return false; |
| } |
| if (IsZipMagic(magic)) { |
| std::unique_ptr<ZipArchive> zip_archive( |
| ZipArchive::OpenFromFd(fd.Release(), filename, error_msg)); |
| if (zip_archive.get() == nullptr) { |
| *error_msg = StringPrintf("Failed to open zip archive '%s' (error msg: %s)", filename, |
| error_msg->c_str()); |
| return false; |
| } |
| |
| uint32_t i = 0; |
| std::string zip_entry_name = GetMultiDexClassesDexName(i++); |
| std::unique_ptr<ZipEntry> zip_entry(zip_archive->Find(zip_entry_name.c_str(), error_msg)); |
| if (zip_entry.get() == nullptr) { |
| *error_msg = StringPrintf("Zip archive '%s' doesn't contain %s (error msg: %s)", filename, |
| zip_entry_name.c_str(), error_msg->c_str()); |
| return false; |
| } |
| |
| do { |
| checksums->push_back(zip_entry->GetCrc32()); |
| zip_entry_name = GetMultiDexClassesDexName(i++); |
| zip_entry.reset(zip_archive->Find(zip_entry_name.c_str(), error_msg)); |
| } while (zip_entry.get() != nullptr); |
| return true; |
| } |
| if (IsValidMagic(magic)) { |
| std::unique_ptr<const DexFile> dex_file( |
| OpenFile(fd.Release(), filename, false, false, error_msg)); |
| if (dex_file == nullptr) { |
| return false; |
| } |
| checksums->push_back(dex_file->GetHeader().checksum_); |
| return true; |
| } |
| *error_msg = StringPrintf("Expected valid zip or dex file: '%s'", filename); |
| return false; |
| } |
| |
| bool DexFileLoader::IsMultiDexLocation(const char* location) { |
| return strrchr(location, kMultiDexSeparator) != nullptr; |
| } |
| |
| std::string DexFileLoader::GetMultiDexClassesDexName(size_t index) { |
| return (index == 0) ? "classes.dex" : StringPrintf("classes%zu.dex", index + 1); |
| } |
| |
| std::string DexFileLoader::GetMultiDexLocation(size_t index, const char* dex_location) { |
| return (index == 0) |
| ? dex_location |
| : StringPrintf("%s%cclasses%zu.dex", dex_location, kMultiDexSeparator, index + 1); |
| } |
| |
| std::string DexFileLoader::GetDexCanonicalLocation(const char* dex_location) { |
| CHECK_NE(dex_location, static_cast<const char*>(nullptr)); |
| std::string base_location = GetBaseLocation(dex_location); |
| const char* suffix = dex_location + base_location.size(); |
| DCHECK(suffix[0] == 0 || suffix[0] == kMultiDexSeparator); |
| UniqueCPtr<const char[]> path(realpath(base_location.c_str(), nullptr)); |
| if (path != nullptr && path.get() != base_location) { |
| return std::string(path.get()) + suffix; |
| } else if (suffix[0] == 0) { |
| return base_location; |
| } else { |
| return dex_location; |
| } |
| } |
| |
| std::unique_ptr<const DexFile> DexFileLoader::Open(const uint8_t* base, |
| size_t size, |
| const std::string& location, |
| uint32_t location_checksum, |
| const OatDexFile* oat_dex_file, |
| bool verify, |
| bool verify_checksum, |
| std::string* error_msg) { |
| ScopedTrace trace(std::string("Open dex file from RAM ") + location); |
| return OpenCommon(base, |
| size, |
| location, |
| location_checksum, |
| oat_dex_file, |
| verify, |
| verify_checksum, |
| error_msg); |
| } |
| |
| std::unique_ptr<const DexFile> DexFileLoader::Open(const std::string& location, |
| uint32_t location_checksum, |
| std::unique_ptr<MemMap> map, |
| bool verify, |
| bool verify_checksum, |
| std::string* error_msg) { |
| ScopedTrace trace(std::string("Open dex file from mapped-memory ") + location); |
| CHECK(map.get() != nullptr); |
| |
| if (map->Size() < sizeof(DexFile::Header)) { |
| *error_msg = StringPrintf( |
| "DexFile: failed to open dex file '%s' that is too short to have a header", |
| location.c_str()); |
| return nullptr; |
| } |
| |
| std::unique_ptr<DexFile> dex_file = OpenCommon(map->Begin(), |
| map->Size(), |
| location, |
| location_checksum, |
| kNoOatDexFile, |
| verify, |
| verify_checksum, |
| error_msg); |
| if (dex_file != nullptr) { |
| dex_file->mem_map_ = std::move(map); |
| } |
| return dex_file; |
| } |
| |
| bool DexFileLoader::Open(const char* filename, |
| const std::string& location, |
| bool verify_checksum, |
| std::string* error_msg, |
| std::vector<std::unique_ptr<const DexFile>>* dex_files) { |
| ScopedTrace trace(std::string("Open dex file ") + std::string(location)); |
| DCHECK(dex_files != nullptr) << "DexFile::Open: out-param is nullptr"; |
| uint32_t magic; |
| File fd = OpenAndReadMagic(filename, &magic, error_msg); |
| if (fd.Fd() == -1) { |
| DCHECK(!error_msg->empty()); |
| return false; |
| } |
| if (IsZipMagic(magic)) { |
| return OpenZip(fd.Release(), location, verify_checksum, error_msg, dex_files); |
| } |
| if (IsValidMagic(magic)) { |
| std::unique_ptr<const DexFile> dex_file(OpenFile(fd.Release(), |
| location, |
| /* verify */ true, |
| verify_checksum, |
| error_msg)); |
| if (dex_file.get() != nullptr) { |
| dex_files->push_back(std::move(dex_file)); |
| return true; |
| } else { |
| return false; |
| } |
| } |
| *error_msg = StringPrintf("Expected valid zip or dex file: '%s'", filename); |
| return false; |
| } |
| |
| std::unique_ptr<const DexFile> DexFileLoader::OpenDex(int fd, |
| const std::string& location, |
| bool verify_checksum, |
| std::string* error_msg) { |
| ScopedTrace trace("Open dex file " + std::string(location)); |
| return OpenFile(fd, location, true /* verify */, verify_checksum, error_msg); |
| } |
| |
| bool DexFileLoader::OpenZip(int fd, |
| const std::string& location, |
| bool verify_checksum, |
| std::string* error_msg, |
| std::vector<std::unique_ptr<const DexFile>>* dex_files) { |
| ScopedTrace trace("Dex file open Zip " + std::string(location)); |
| DCHECK(dex_files != nullptr) << "DexFile::OpenZip: out-param is nullptr"; |
| std::unique_ptr<ZipArchive> zip_archive(ZipArchive::OpenFromFd(fd, location.c_str(), error_msg)); |
| if (zip_archive.get() == nullptr) { |
| DCHECK(!error_msg->empty()); |
| return false; |
| } |
| return OpenAllDexFilesFromZip(*zip_archive, location, verify_checksum, error_msg, dex_files); |
| } |
| |
| std::unique_ptr<const DexFile> DexFileLoader::OpenFile(int fd, |
| const std::string& location, |
| bool verify, |
| bool verify_checksum, |
| std::string* error_msg) { |
| ScopedTrace trace(std::string("Open dex file ") + std::string(location)); |
| CHECK(!location.empty()); |
| std::unique_ptr<MemMap> map; |
| { |
| File delayed_close(fd, /* check_usage */ false); |
| struct stat sbuf; |
| memset(&sbuf, 0, sizeof(sbuf)); |
| if (fstat(fd, &sbuf) == -1) { |
| *error_msg = StringPrintf("DexFile: fstat '%s' failed: %s", location.c_str(), |
| strerror(errno)); |
| return nullptr; |
| } |
| if (S_ISDIR(sbuf.st_mode)) { |
| *error_msg = StringPrintf("Attempt to mmap directory '%s'", location.c_str()); |
| return nullptr; |
| } |
| size_t length = sbuf.st_size; |
| map.reset(MemMap::MapFile(length, |
| PROT_READ, |
| MAP_PRIVATE, |
| fd, |
| 0, |
| /*low_4gb*/false, |
| location.c_str(), |
| error_msg)); |
| if (map == nullptr) { |
| DCHECK(!error_msg->empty()); |
| return nullptr; |
| } |
| } |
| |
| if (map->Size() < sizeof(DexFile::Header)) { |
| *error_msg = StringPrintf( |
| "DexFile: failed to open dex file '%s' that is too short to have a header", |
| location.c_str()); |
| return nullptr; |
| } |
| |
| const DexFile::Header* dex_header = reinterpret_cast<const DexFile::Header*>(map->Begin()); |
| |
| std::unique_ptr<DexFile> dex_file = OpenCommon(map->Begin(), |
| map->Size(), |
| location, |
| dex_header->checksum_, |
| kNoOatDexFile, |
| verify, |
| verify_checksum, |
| error_msg); |
| if (dex_file != nullptr) { |
| dex_file->mem_map_ = std::move(map); |
| } |
| |
| return dex_file; |
| } |
| |
| std::unique_ptr<const DexFile> DexFileLoader::OpenOneDexFileFromZip( |
| const ZipArchive& zip_archive, |
| const char* entry_name, |
| const std::string& location, |
| bool verify_checksum, |
| std::string* error_msg, |
| ZipOpenErrorCode* error_code) { |
| ScopedTrace trace("Dex file open from Zip Archive " + std::string(location)); |
| CHECK(!location.empty()); |
| std::unique_ptr<ZipEntry> zip_entry(zip_archive.Find(entry_name, error_msg)); |
| if (zip_entry == nullptr) { |
| *error_code = ZipOpenErrorCode::kEntryNotFound; |
| return nullptr; |
| } |
| if (zip_entry->GetUncompressedLength() == 0) { |
| *error_msg = StringPrintf("Dex file '%s' has zero length", location.c_str()); |
| *error_code = ZipOpenErrorCode::kDexFileError; |
| return nullptr; |
| } |
| |
| std::unique_ptr<MemMap> map; |
| if (zip_entry->IsUncompressed()) { |
| if (!zip_entry->IsAlignedTo(alignof(DexFile::Header))) { |
| // Do not mmap unaligned ZIP entries because |
| // doing so would fail dex verification which requires 4 byte alignment. |
| LOG(WARNING) << "Can't mmap dex file " << location << "!" << entry_name << " directly; " |
| << "please zipalign to " << alignof(DexFile::Header) << " bytes. " |
| << "Falling back to extracting file."; |
| } else { |
| // Map uncompressed files within zip as file-backed to avoid a dirty copy. |
| map.reset(zip_entry->MapDirectlyFromFile(location.c_str(), /*out*/error_msg)); |
| if (map == nullptr) { |
| LOG(WARNING) << "Can't mmap dex file " << location << "!" << entry_name << " directly; " |
| << "is your ZIP file corrupted? Falling back to extraction."; |
| // Try again with Extraction which still has a chance of recovery. |
| } |
| } |
| } |
| |
| if (map == nullptr) { |
| // Default path for compressed ZIP entries, |
| // and fallback for stored ZIP entries. |
| map.reset(zip_entry->ExtractToMemMap(location.c_str(), entry_name, error_msg)); |
| } |
| |
| if (map == nullptr) { |
| *error_msg = StringPrintf("Failed to extract '%s' from '%s': %s", entry_name, location.c_str(), |
| error_msg->c_str()); |
| *error_code = ZipOpenErrorCode::kExtractToMemoryError; |
| return nullptr; |
| } |
| VerifyResult verify_result; |
| std::unique_ptr<DexFile> dex_file = OpenCommon(map->Begin(), |
| map->Size(), |
| location, |
| zip_entry->GetCrc32(), |
| kNoOatDexFile, |
| /* verify */ true, |
| verify_checksum, |
| error_msg, |
| &verify_result); |
| if (dex_file == nullptr) { |
| if (verify_result == VerifyResult::kVerifyNotAttempted) { |
| *error_code = ZipOpenErrorCode::kDexFileError; |
| } else { |
| *error_code = ZipOpenErrorCode::kVerifyError; |
| } |
| return nullptr; |
| } |
| dex_file->mem_map_ = std::move(map); |
| if (!dex_file->DisableWrite()) { |
| *error_msg = StringPrintf("Failed to make dex file '%s' read only", location.c_str()); |
| *error_code = ZipOpenErrorCode::kMakeReadOnlyError; |
| return nullptr; |
| } |
| CHECK(dex_file->IsReadOnly()) << location; |
| if (verify_result != VerifyResult::kVerifySucceeded) { |
| *error_code = ZipOpenErrorCode::kVerifyError; |
| return nullptr; |
| } |
| *error_code = ZipOpenErrorCode::kNoError; |
| return dex_file; |
| } |
| |
| // Technically we do not have a limitation with respect to the number of dex files that can be in a |
| // multidex APK. However, it's bad practice, as each dex file requires its own tables for symbols |
| // (types, classes, methods, ...) and dex caches. So warn the user that we open a zip with what |
| // seems an excessive number. |
| static constexpr size_t kWarnOnManyDexFilesThreshold = 100; |
| |
| bool DexFileLoader::OpenAllDexFilesFromZip(const ZipArchive& zip_archive, |
| const std::string& location, |
| bool verify_checksum, |
| std::string* error_msg, |
| std::vector<std::unique_ptr<const DexFile>>* dex_files) { |
| ScopedTrace trace("Dex file open from Zip " + std::string(location)); |
| DCHECK(dex_files != nullptr) << "DexFile::OpenFromZip: out-param is nullptr"; |
| ZipOpenErrorCode error_code; |
| std::unique_ptr<const DexFile> dex_file(OpenOneDexFileFromZip(zip_archive, |
| kClassesDex, |
| location, |
| verify_checksum, |
| error_msg, |
| &error_code)); |
| if (dex_file.get() == nullptr) { |
| return false; |
| } else { |
| // Had at least classes.dex. |
| dex_files->push_back(std::move(dex_file)); |
| |
| // Now try some more. |
| |
| // We could try to avoid std::string allocations by working on a char array directly. As we |
| // do not expect a lot of iterations, this seems too involved and brittle. |
| |
| for (size_t i = 1; ; ++i) { |
| std::string name = GetMultiDexClassesDexName(i); |
| std::string fake_location = GetMultiDexLocation(i, location.c_str()); |
| std::unique_ptr<const DexFile> next_dex_file(OpenOneDexFileFromZip(zip_archive, |
| name.c_str(), |
| fake_location, |
| verify_checksum, |
| error_msg, |
| &error_code)); |
| if (next_dex_file.get() == nullptr) { |
| if (error_code != ZipOpenErrorCode::kEntryNotFound) { |
| LOG(WARNING) << "Zip open failed: " << *error_msg; |
| } |
| break; |
| } else { |
| dex_files->push_back(std::move(next_dex_file)); |
| } |
| |
| if (i == kWarnOnManyDexFilesThreshold) { |
| LOG(WARNING) << location << " has in excess of " << kWarnOnManyDexFilesThreshold |
| << " dex files. Please consider coalescing and shrinking the number to " |
| " avoid runtime overhead."; |
| } |
| |
| if (i == std::numeric_limits<size_t>::max()) { |
| LOG(ERROR) << "Overflow in number of dex files!"; |
| break; |
| } |
| } |
| |
| return true; |
| } |
| } |
| |
| std::unique_ptr<DexFile> DexFileLoader::OpenCommon(const uint8_t* base, |
| size_t size, |
| const std::string& location, |
| uint32_t location_checksum, |
| const OatDexFile* oat_dex_file, |
| bool verify, |
| bool verify_checksum, |
| std::string* error_msg, |
| VerifyResult* verify_result) { |
| if (verify_result != nullptr) { |
| *verify_result = VerifyResult::kVerifyNotAttempted; |
| } |
| std::unique_ptr<DexFile> dex_file; |
| if (NativeDexFile::IsMagicValid(base)) { |
| dex_file.reset(new NativeDexFile(base, size, location, location_checksum, oat_dex_file)); |
| } else { |
| return nullptr; |
| } |
| if (dex_file == nullptr) { |
| *error_msg = StringPrintf("Failed to open dex file '%s' from memory: %s", location.c_str(), |
| error_msg->c_str()); |
| return nullptr; |
| } |
| if (!dex_file->Init(error_msg)) { |
| dex_file.reset(); |
| return nullptr; |
| } |
| if (verify && !DexFileVerifier::Verify(dex_file.get(), |
| dex_file->Begin(), |
| dex_file->Size(), |
| location.c_str(), |
| verify_checksum, |
| error_msg)) { |
| if (verify_result != nullptr) { |
| *verify_result = VerifyResult::kVerifyFailed; |
| } |
| return nullptr; |
| } |
| if (verify_result != nullptr) { |
| *verify_result = VerifyResult::kVerifySucceeded; |
| } |
| return dex_file; |
| } |
| |
| } // namespace art |