| /* |
| * 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. |
| */ |
| |
| #define ATRACE_TAG ATRACE_TAG_RESOURCES |
| |
| #include "androidfw/Idmap.h" |
| |
| #include "android-base/logging.h" |
| #include "android-base/stringprintf.h" |
| #include "androidfw/misc.h" |
| #include "androidfw/ResourceTypes.h" |
| #include "androidfw/Util.h" |
| #include "utils/ByteOrder.h" |
| #include "utils/Trace.h" |
| |
| #ifdef _WIN32 |
| #ifdef ERROR |
| #undef ERROR |
| #endif |
| #endif |
| |
| using ::android::base::StringPrintf; |
| |
| namespace android { |
| |
| uint32_t round_to_4_bytes(uint32_t size) { |
| return size + (4U - (size % 4U)) % 4U; |
| } |
| |
| size_t Idmap_header::Size() const { |
| return sizeof(Idmap_header) + sizeof(uint8_t) * round_to_4_bytes(dtohl(debug_info_size)); |
| } |
| |
| OverlayStringPool::OverlayStringPool(const LoadedIdmap* loaded_idmap) |
| : data_header_(loaded_idmap->data_header_), |
| idmap_string_pool_(loaded_idmap->string_pool_.get()) { }; |
| |
| OverlayStringPool::~OverlayStringPool() { |
| uninit(); |
| } |
| |
| base::expected<StringPiece16, NullOrIOError> OverlayStringPool::stringAt(size_t idx) const { |
| const size_t offset = dtohl(data_header_->string_pool_index_offset); |
| if (idmap_string_pool_ != nullptr && idx >= ResStringPool::size() && idx >= offset) { |
| return idmap_string_pool_->stringAt(idx - offset); |
| } |
| |
| return ResStringPool::stringAt(idx); |
| } |
| |
| base::expected<StringPiece, NullOrIOError> OverlayStringPool::string8At(size_t idx) const { |
| const size_t offset = dtohl(data_header_->string_pool_index_offset); |
| if (idmap_string_pool_ != nullptr && idx >= ResStringPool::size() && idx >= offset) { |
| return idmap_string_pool_->string8At(idx - offset); |
| } |
| |
| return ResStringPool::string8At(idx); |
| } |
| |
| size_t OverlayStringPool::size() const { |
| return ResStringPool::size() + (idmap_string_pool_ != nullptr ? idmap_string_pool_->size() : 0U); |
| } |
| |
| OverlayDynamicRefTable::OverlayDynamicRefTable(const Idmap_data_header* data_header, |
| const Idmap_overlay_entry* entries, |
| uint8_t target_assigned_package_id) |
| : data_header_(data_header), |
| entries_(entries), |
| target_assigned_package_id_(target_assigned_package_id) { }; |
| |
| status_t OverlayDynamicRefTable::lookupResourceId(uint32_t* resId) const { |
| const Idmap_overlay_entry* first_entry = entries_; |
| const Idmap_overlay_entry* end_entry = entries_ + dtohl(data_header_->overlay_entry_count); |
| auto entry = std::lower_bound(first_entry, end_entry, *resId, |
| [](const Idmap_overlay_entry& e1, const uint32_t overlay_id) { |
| return dtohl(e1.overlay_id) < overlay_id; |
| }); |
| |
| if (entry == end_entry || dtohl(entry->overlay_id) != *resId) { |
| // A mapping for the target resource id could not be found. |
| return DynamicRefTable::lookupResourceId(resId); |
| } |
| |
| *resId = (0x00FFFFFFU & dtohl(entry->target_id)) |
| | (((uint32_t) target_assigned_package_id_) << 24U); |
| return NO_ERROR; |
| } |
| |
| status_t OverlayDynamicRefTable::lookupResourceIdNoRewrite(uint32_t* resId) const { |
| return DynamicRefTable::lookupResourceId(resId); |
| } |
| |
| IdmapResMap::IdmapResMap(const Idmap_data_header* data_header, |
| const Idmap_target_entry* entries, |
| const Idmap_target_entry_inline* inline_entries, |
| uint8_t target_assigned_package_id, |
| const OverlayDynamicRefTable* overlay_ref_table) |
| : data_header_(data_header), |
| entries_(entries), |
| inline_entries_(inline_entries), |
| target_assigned_package_id_(target_assigned_package_id), |
| overlay_ref_table_(overlay_ref_table) { } |
| |
| IdmapResMap::Result IdmapResMap::Lookup(uint32_t target_res_id) const { |
| if ((target_res_id >> 24U) != target_assigned_package_id_) { |
| // The resource id must have the same package id as the target package. |
| return {}; |
| } |
| |
| // The resource ids encoded within the idmap are build-time resource ids. |
| target_res_id = (0x00FFFFFFU & target_res_id) |
| | (((uint32_t) data_header_->target_package_id) << 24U); |
| |
| // Check if the target resource is mapped to an overlay resource. |
| auto first_entry = entries_; |
| auto end_entry = entries_ + dtohl(data_header_->target_entry_count); |
| auto entry = std::lower_bound(first_entry, end_entry, target_res_id, |
| [](const Idmap_target_entry &e, const uint32_t target_id) { |
| return dtohl(e.target_id) < target_id; |
| }); |
| |
| if (entry != end_entry && dtohl(entry->target_id) == target_res_id) { |
| uint32_t overlay_resource_id = dtohl(entry->overlay_id); |
| // Lookup the resource without rewriting the overlay resource id back to the target resource id |
| // being looked up. |
| overlay_ref_table_->lookupResourceIdNoRewrite(&overlay_resource_id); |
| return Result(overlay_resource_id); |
| } |
| |
| // Check if the target resources is mapped to an inline table entry. |
| auto first_inline_entry = inline_entries_; |
| auto end_inline_entry = inline_entries_ + dtohl(data_header_->target_inline_entry_count); |
| auto inline_entry = std::lower_bound(first_inline_entry, end_inline_entry, target_res_id, |
| [](const Idmap_target_entry_inline &e, |
| const uint32_t target_id) { |
| return dtohl(e.target_id) < target_id; |
| }); |
| |
| if (inline_entry != end_inline_entry && dtohl(inline_entry->target_id) == target_res_id) { |
| return Result(inline_entry->value); |
| } |
| return {}; |
| } |
| |
| static bool is_word_aligned(const void* data) { |
| return (reinterpret_cast<uintptr_t>(data) & 0x03U) == 0U; |
| } |
| |
| static bool IsValidIdmapHeader(const StringPiece& data) { |
| if (!is_word_aligned(data.data())) { |
| LOG(ERROR) << "Idmap header is not word aligned."; |
| return false; |
| } |
| |
| if (data.size() < sizeof(Idmap_header)) { |
| LOG(ERROR) << "Idmap header is too small."; |
| return false; |
| } |
| |
| auto header = reinterpret_cast<const Idmap_header*>(data.data()); |
| if (dtohl(header->magic) != kIdmapMagic) { |
| LOG(ERROR) << StringPrintf("Invalid Idmap file: bad magic value (was 0x%08x, expected 0x%08x)", |
| dtohl(header->magic), kIdmapMagic); |
| return false; |
| } |
| |
| if (dtohl(header->version) != kIdmapCurrentVersion) { |
| // We are strict about versions because files with this format are auto-generated and don't need |
| // backwards compatibility. |
| LOG(ERROR) << StringPrintf("Version mismatch in Idmap (was 0x%08x, expected 0x%08x)", |
| dtohl(header->version), kIdmapCurrentVersion); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| LoadedIdmap::LoadedIdmap(std::string&& idmap_path, |
| const time_t last_mod_time, |
| const Idmap_header* header, |
| const Idmap_data_header* data_header, |
| const Idmap_target_entry* target_entries, |
| const Idmap_target_entry_inline* target_inline_entries, |
| const Idmap_overlay_entry* overlay_entries, |
| ResStringPool* string_pool) |
| : header_(header), |
| data_header_(data_header), |
| target_entries_(target_entries), |
| target_inline_entries_(target_inline_entries), |
| overlay_entries_(overlay_entries), |
| string_pool_(string_pool), |
| idmap_path_(std::move(idmap_path)), |
| idmap_last_mod_time_(last_mod_time) { |
| |
| size_t length = strnlen(reinterpret_cast<const char*>(header_->overlay_path), |
| arraysize(header_->overlay_path)); |
| overlay_apk_path_.assign(reinterpret_cast<const char*>(header_->overlay_path), length); |
| |
| length = strnlen(reinterpret_cast<const char*>(header_->target_path), |
| arraysize(header_->target_path)); |
| target_apk_path_.assign(reinterpret_cast<const char*>(header_->target_path), length); |
| } |
| |
| std::unique_ptr<const LoadedIdmap> LoadedIdmap::Load(const StringPiece& idmap_path, |
| const StringPiece& idmap_data) { |
| ATRACE_CALL(); |
| if (!IsValidIdmapHeader(idmap_data)) { |
| return {}; |
| } |
| |
| auto header = reinterpret_cast<const Idmap_header*>(idmap_data.data()); |
| const uint8_t* data_ptr = reinterpret_cast<const uint8_t*>(idmap_data.data()) + header->Size(); |
| size_t data_size = idmap_data.size() - header->Size(); |
| |
| // Currently idmap2 can only generate one data block. |
| auto data_header = reinterpret_cast<const Idmap_data_header*>(data_ptr); |
| data_ptr += sizeof(*data_header); |
| data_size -= sizeof(*data_header); |
| |
| // Make sure there is enough space for the target entries declared in the header |
| const auto target_entries = reinterpret_cast<const Idmap_target_entry*>(data_ptr); |
| if (data_size / sizeof(Idmap_target_entry) < |
| static_cast<size_t>(dtohl(data_header->target_entry_count))) { |
| LOG(ERROR) << StringPrintf("Idmap too small for the number of target entries (%d)", |
| (int)dtohl(data_header->target_entry_count)); |
| return {}; |
| } |
| |
| // Advance the data pointer past the target entries. |
| const size_t target_entry_size_bytes = |
| (dtohl(data_header->target_entry_count) * sizeof(Idmap_target_entry)); |
| data_ptr += target_entry_size_bytes; |
| data_size -= target_entry_size_bytes; |
| |
| // Make sure there is enough space for the target entries declared in the header. |
| const auto target_inline_entries = reinterpret_cast<const Idmap_target_entry_inline*>(data_ptr); |
| if (data_size / sizeof(Idmap_target_entry_inline) < |
| static_cast<size_t>(dtohl(data_header->target_inline_entry_count))) { |
| LOG(ERROR) << StringPrintf("Idmap too small for the number of target inline entries (%d)", |
| (int)dtohl(data_header->target_inline_entry_count)); |
| return {}; |
| } |
| |
| // Advance the data pointer past the target entries. |
| const size_t target_inline_entry_size_bytes = |
| (dtohl(data_header->target_inline_entry_count) * sizeof(Idmap_target_entry_inline)); |
| data_ptr += target_inline_entry_size_bytes; |
| data_size -= target_inline_entry_size_bytes; |
| |
| // Make sure there is enough space for the overlay entries declared in the header. |
| const auto overlay_entries = reinterpret_cast<const Idmap_overlay_entry*>(data_ptr); |
| if (data_size / sizeof(Idmap_overlay_entry) < |
| static_cast<size_t>(dtohl(data_header->overlay_entry_count))) { |
| LOG(ERROR) << StringPrintf("Idmap too small for the number of overlay entries (%d)", |
| (int)dtohl(data_header->overlay_entry_count)); |
| return {}; |
| } |
| |
| // Advance the data pointer past the overlay entries. |
| const size_t overlay_entry_size_bytes = |
| (dtohl(data_header->overlay_entry_count) * sizeof(Idmap_overlay_entry)); |
| data_ptr += overlay_entry_size_bytes; |
| data_size -= overlay_entry_size_bytes; |
| |
| // Read the idmap string pool that holds the value of inline string entries. |
| uint32_t string_pool_size = dtohl(*reinterpret_cast<const uint32_t*>(data_ptr)); |
| data_ptr += sizeof(uint32_t); |
| data_size -= sizeof(uint32_t); |
| |
| if (data_size < string_pool_size) { |
| LOG(ERROR) << StringPrintf("Idmap too small for string pool (length %d)", |
| (int)string_pool_size); |
| return {}; |
| } |
| |
| auto idmap_string_pool = util::make_unique<ResStringPool>(); |
| if (string_pool_size > 0) { |
| status_t err = idmap_string_pool->setTo(data_ptr, string_pool_size); |
| if (err != NO_ERROR) { |
| LOG(ERROR) << "idmap string pool corrupt."; |
| return {}; |
| } |
| } |
| |
| // Can't use make_unique because LoadedIdmap constructor is private. |
| auto loaded_idmap = std::unique_ptr<LoadedIdmap>( |
| new LoadedIdmap(idmap_path.to_string(), getFileModDate(idmap_path.data()), header, |
| data_header, target_entries, target_inline_entries, overlay_entries, |
| idmap_string_pool.release())); |
| |
| return std::move(loaded_idmap); |
| } |
| |
| bool LoadedIdmap::IsUpToDate() const { |
| return idmap_last_mod_time_ == getFileModDate(idmap_path_.c_str()); |
| } |
| |
| } // namespace android |