blob: 1a82021bce71f1b665775599ec00fcdcf4094180 [file] [log] [blame]
/*
* Copyright (C) 2015 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 "format/binary/TableFlattener.h"
#include <limits>
#include <sstream>
#include <type_traits>
#include <variant>
#include "ResourceTable.h"
#include "ResourceValues.h"
#include "SdkConstants.h"
#include "android-base/logging.h"
#include "android-base/macros.h"
#include "android-base/stringprintf.h"
#include "androidfw/BigBuffer.h"
#include "androidfw/ResourceUtils.h"
#include "format/binary/ChunkWriter.h"
#include "format/binary/ResEntryWriter.h"
#include "format/binary/ResourceTypeExtensions.h"
#include "optimize/Obfuscator.h"
#include "trace/TraceBuffer.h"
using namespace android;
namespace aapt {
namespace {
template <typename T>
static bool cmp_ids(const T* a, const T* b) {
return a->id.value() < b->id.value();
}
static void strcpy16_htod(uint16_t* dst, size_t len, const StringPiece16& src) {
if (len == 0) {
return;
}
size_t i;
const char16_t* src_data = src.data();
for (i = 0; i < len - 1 && i < src.size(); i++) {
dst[i] = android::util::HostToDevice16((uint16_t)src_data[i]);
}
dst[i] = 0;
}
struct OverlayableChunk {
std::string actor;
android::Source source;
std::map<PolicyFlags, std::set<ResourceId>> policy_ids;
};
class PackageFlattener {
public:
PackageFlattener(IAaptContext* context, const ResourceTablePackageView& package,
const ResourceTable::ReferencedPackages* shared_libs,
SparseEntriesMode sparse_entries, bool compact_entries,
bool collapse_key_stringpool,
const std::set<ResourceName>& name_collapse_exemptions,
bool deduplicate_entry_values)
: context_(context),
diag_(context->GetDiagnostics()),
package_(package),
shared_libs_(shared_libs),
sparse_entries_(sparse_entries),
compact_entries_(compact_entries),
collapse_key_stringpool_(collapse_key_stringpool),
name_collapse_exemptions_(name_collapse_exemptions),
deduplicate_entry_values_(deduplicate_entry_values) {
}
bool FlattenPackage(BigBuffer* buffer) {
TRACE_CALL();
ChunkWriter pkg_writer(buffer);
ResTable_package* pkg_header = pkg_writer.StartChunk<ResTable_package>(RES_TABLE_PACKAGE_TYPE);
pkg_header->id = android::util::HostToDevice32(package_.id.value());
// AAPT truncated the package name, so do the same.
// Shared libraries require full package names, so don't truncate theirs.
if (context_->GetPackageType() != PackageType::kApp &&
package_.name.size() >= arraysize(pkg_header->name)) {
diag_->Error(android::DiagMessage()
<< "package name '" << package_.name
<< "' is too long. "
"Shared libraries cannot have truncated package names");
return false;
}
// Copy the package name in device endianness.
strcpy16_htod(pkg_header->name, arraysize(pkg_header->name),
android::util::Utf8ToUtf16(package_.name));
// Serialize the types. We do this now so that our type and key strings
// are populated. We write those first.
android::BigBuffer type_buffer(1024);
FlattenTypes(&type_buffer);
pkg_header->typeStrings = android::util::HostToDevice32(pkg_writer.size());
android::StringPool::FlattenUtf16(pkg_writer.buffer(), type_pool_, diag_);
pkg_header->keyStrings = android::util::HostToDevice32(pkg_writer.size());
android::StringPool::FlattenUtf8(pkg_writer.buffer(), key_pool_, diag_);
// Append the types.
buffer->AppendBuffer(std::move(type_buffer));
// If there are libraries (or if the package ID is 0x00), encode a library chunk.
if (package_.id.value() == 0x00 || !shared_libs_->empty()) {
FlattenLibrarySpec(buffer);
}
if (!FlattenOverlayable(buffer)) {
return false;
}
if (!FlattenAliases(buffer)) {
return false;
}
pkg_writer.Finish();
return true;
}
private:
DISALLOW_COPY_AND_ASSIGN(PackageFlattener);
// Use compact entries only if
// 1) it is enabled, and that
// 2) the entries will be accessed on platforms U+, and
// 3) all entry keys can be encoded in 16 bits
bool UseCompactEntries(const ConfigDescription& config, std::vector<FlatEntry>* entries) const {
return compact_entries_ && context_->GetMinSdkVersion() > SDK_TIRAMISU &&
std::none_of(entries->cbegin(), entries->cend(),
[](const auto& e) { return e.entry_key >= std::numeric_limits<uint16_t>::max(); });
}
std::unique_ptr<ResEntryWriter> GetResEntryWriter(bool dedup, bool compact, BigBuffer* buffer) {
if (dedup) {
if (compact) {
return std::make_unique<DeduplicateItemsResEntryWriter<true>>(buffer);
} else {
return std::make_unique<DeduplicateItemsResEntryWriter<false>>(buffer);
}
} else {
if (compact) {
return std::make_unique<SequentialResEntryWriter<true>>(buffer);
} else {
return std::make_unique<SequentialResEntryWriter<false>>(buffer);
}
}
}
bool FlattenConfig(const ResourceTableTypeView& type, const ConfigDescription& config,
const size_t num_total_entries, std::vector<FlatEntry>* entries,
BigBuffer* buffer) {
CHECK(num_total_entries != 0);
CHECK(num_total_entries <= std::numeric_limits<uint16_t>::max());
ChunkWriter type_writer(buffer);
ResTable_type* type_header = type_writer.StartChunk<ResTable_type>(RES_TABLE_TYPE_TYPE);
type_header->id = type.id.value();
type_header->config = config;
type_header->config.swapHtoD();
std::vector<uint32_t> offsets;
offsets.resize(num_total_entries, 0xffffffffu);
bool compact_entry = UseCompactEntries(config, entries);
android::BigBuffer values_buffer(512);
auto res_entry_writer = GetResEntryWriter(deduplicate_entry_values_,
compact_entry, &values_buffer);
for (FlatEntry& flat_entry : *entries) {
CHECK(static_cast<size_t>(flat_entry.entry->id.value()) < num_total_entries);
offsets[flat_entry.entry->id.value()] = res_entry_writer->Write(&flat_entry);
}
// whether the offsets can be represented in 2 bytes
bool short_offsets = (values_buffer.size() / 4u) < std::numeric_limits<uint16_t>::max();
bool sparse_encode = sparse_entries_ == SparseEntriesMode::Enabled ||
sparse_entries_ == SparseEntriesMode::Forced;
if (sparse_entries_ == SparseEntriesMode::Forced ||
(context_->GetMinSdkVersion() == 0 && config.sdkVersion == 0)) {
// Sparse encode if forced or sdk version is not set in context and config.
} else {
// Otherwise, only sparse encode if the entries will be read on platforms S_V2+.
sparse_encode = sparse_encode && (context_->GetMinSdkVersion() >= SDK_S_V2);
}
// Only sparse encode if the offsets are representable in 2 bytes.
sparse_encode = sparse_encode && short_offsets;
// Only sparse encode if the ratio of populated entries to total entries is below some
// threshold.
sparse_encode =
sparse_encode && ((100 * entries->size()) / num_total_entries) < kSparseEncodingThreshold;
if (sparse_encode) {
type_header->entryCount = android::util::HostToDevice32(entries->size());
type_header->flags |= ResTable_type::FLAG_SPARSE;
ResTable_sparseTypeEntry* indices =
type_writer.NextBlock<ResTable_sparseTypeEntry>(entries->size());
for (size_t i = 0; i < num_total_entries; i++) {
if (offsets[i] != ResTable_type::NO_ENTRY) {
CHECK((offsets[i] & 0x03) == 0);
indices->idx = android::util::HostToDevice16(i);
indices->offset = android::util::HostToDevice16(offsets[i] / 4u);
indices++;
}
}
} else {
type_header->entryCount = android::util::HostToDevice32(num_total_entries);
if (compact_entry && short_offsets) {
// use 16-bit offset only when compact_entry is true
type_header->flags |= ResTable_type::FLAG_OFFSET16;
uint16_t* indices = type_writer.NextBlock<uint16_t>(num_total_entries);
for (size_t i = 0; i < num_total_entries; i++) {
indices[i] = android::util::HostToDevice16(offsets[i] / 4u);
}
} else {
uint32_t* indices = type_writer.NextBlock<uint32_t>(num_total_entries);
for (size_t i = 0; i < num_total_entries; i++) {
indices[i] = android::util::HostToDevice32(offsets[i]);
}
}
}
type_writer.buffer()->Align4();
type_header->entriesStart = android::util::HostToDevice32(type_writer.size());
type_writer.buffer()->AppendBuffer(std::move(values_buffer));
type_writer.Finish();
return true;
}
bool FlattenAliases(BigBuffer* buffer) {
if (aliases_.empty()) {
return true;
}
ChunkWriter alias_writer(buffer);
auto header =
alias_writer.StartChunk<ResTable_staged_alias_header>(RES_TABLE_STAGED_ALIAS_TYPE);
header->count = android::util::HostToDevice32(aliases_.size());
auto mapping = alias_writer.NextBlock<ResTable_staged_alias_entry>(aliases_.size());
for (auto& p : aliases_) {
mapping->stagedResId = android::util::HostToDevice32(p.first);
mapping->finalizedResId = android::util::HostToDevice32(p.second);
++mapping;
}
alias_writer.Finish();
return true;
}
bool FlattenOverlayable(BigBuffer* buffer) {
std::set<ResourceId> seen_ids;
std::map<std::string, OverlayableChunk> overlayable_chunks;
CHECK(bool(package_.id)) << "package must have an ID set when flattening <overlayable>";
for (auto& type : package_.types) {
CHECK(bool(type.id)) << "type must have an ID set when flattening <overlayable>";
for (auto& entry : type.entries) {
CHECK(bool(type.id)) << "entry must have an ID set when flattening <overlayable>";
if (!entry.overlayable_item) {
continue;
}
const OverlayableItem& item = entry.overlayable_item.value();
// Resource ids should only appear once in the resource table
ResourceId id = android::make_resid(package_.id.value(), type.id.value(), entry.id.value());
CHECK(seen_ids.find(id) == seen_ids.end())
<< "multiple overlayable definitions found for resource "
<< ResourceName(package_.name, type.named_type, entry.name).to_string();
seen_ids.insert(id);
// Find the overlayable chunk with the specified name
OverlayableChunk* overlayable_chunk = nullptr;
auto iter = overlayable_chunks.find(item.overlayable->name);
if (iter == overlayable_chunks.end()) {
OverlayableChunk chunk{item.overlayable->actor, item.overlayable->source};
overlayable_chunk =
&overlayable_chunks.insert({item.overlayable->name, chunk}).first->second;
} else {
OverlayableChunk& chunk = iter->second;
if (!(chunk.source == item.overlayable->source)) {
// The name of an overlayable set of resources must be unique
context_->GetDiagnostics()->Error(android::DiagMessage(item.overlayable->source)
<< "duplicate overlayable name"
<< item.overlayable->name << "'");
context_->GetDiagnostics()->Error(android::DiagMessage(chunk.source)
<< "previous declaration here");
return false;
}
CHECK(chunk.actor == item.overlayable->actor);
overlayable_chunk = &chunk;
}
if (item.policies == 0) {
context_->GetDiagnostics()->Error(android::DiagMessage(item.overlayable->source)
<< "overlayable " << entry.name
<< " does not specify policy");
return false;
}
auto policy = overlayable_chunk->policy_ids.find(item.policies);
if (policy != overlayable_chunk->policy_ids.end()) {
policy->second.insert(id);
} else {
overlayable_chunk->policy_ids.insert(
std::make_pair(item.policies, std::set<ResourceId>{id}));
}
}
}
for (auto& overlayable_pair : overlayable_chunks) {
std::string name = overlayable_pair.first;
OverlayableChunk& overlayable = overlayable_pair.second;
// Write the header of the overlayable chunk
ChunkWriter overlayable_writer(buffer);
auto* overlayable_type =
overlayable_writer.StartChunk<ResTable_overlayable_header>(RES_TABLE_OVERLAYABLE_TYPE);
if (name.size() >= arraysize(overlayable_type->name)) {
diag_->Error(android::DiagMessage()
<< "overlayable name '" << name << "' exceeds maximum length ("
<< arraysize(overlayable_type->name) << " utf16 characters)");
return false;
}
strcpy16_htod(overlayable_type->name, arraysize(overlayable_type->name),
android::util::Utf8ToUtf16(name));
if (overlayable.actor.size() >= arraysize(overlayable_type->actor)) {
diag_->Error(android::DiagMessage()
<< "overlayable name '" << overlayable.actor << "' exceeds maximum length ("
<< arraysize(overlayable_type->actor) << " utf16 characters)");
return false;
}
strcpy16_htod(overlayable_type->actor, arraysize(overlayable_type->actor),
android::util::Utf8ToUtf16(overlayable.actor));
// Write each policy block for the overlayable
for (auto& policy_ids : overlayable.policy_ids) {
ChunkWriter policy_writer(buffer);
auto* policy_type = policy_writer.StartChunk<ResTable_overlayable_policy_header>(
RES_TABLE_OVERLAYABLE_POLICY_TYPE);
policy_type->policy_flags = static_cast<PolicyFlags>(
android::util::HostToDevice32(static_cast<uint32_t>(policy_ids.first)));
policy_type->entry_count =
android::util::HostToDevice32(static_cast<uint32_t>(policy_ids.second.size()));
// Write the ids after the policy header
auto* id_block = policy_writer.NextBlock<ResTable_ref>(policy_ids.second.size());
for (const ResourceId& id : policy_ids.second) {
id_block->ident = android::util::HostToDevice32(id.id);
id_block++;
}
policy_writer.Finish();
}
overlayable_writer.Finish();
}
return true;
}
ResTable_typeSpec* FlattenTypeSpec(const ResourceTableTypeView& type,
const std::vector<ResourceTableEntryView>& sorted_entries,
BigBuffer* buffer) {
ChunkWriter type_spec_writer(buffer);
ResTable_typeSpec* spec_header =
type_spec_writer.StartChunk<ResTable_typeSpec>(RES_TABLE_TYPE_SPEC_TYPE);
spec_header->id = type.id.value();
if (sorted_entries.empty()) {
type_spec_writer.Finish();
return spec_header;
}
// We can't just take the size of the vector. There may be holes in the
// entry ID space.
// Since the entries are sorted by ID, the last one will be the biggest.
const size_t num_entries = sorted_entries.back().id.value() + 1;
spec_header->entryCount = android::util::HostToDevice32(num_entries);
// Reserve space for the masks of each resource in this type. These
// show for which configuration axis the resource changes.
uint32_t* config_masks = type_spec_writer.NextBlock<uint32_t>(num_entries);
for (const ResourceTableEntryView& entry : sorted_entries) {
const uint16_t entry_id = entry.id.value();
// Populate the config masks for this entry.
uint32_t& entry_config_masks = config_masks[entry_id];
if (entry.visibility.level == Visibility::Level::kPublic) {
entry_config_masks |= android::util::HostToDevice32(ResTable_typeSpec::SPEC_PUBLIC);
}
if (entry.visibility.staged_api) {
entry_config_masks |= android::util::HostToDevice32(ResTable_typeSpec::SPEC_STAGED_API);
}
const size_t config_count = entry.values.size();
for (size_t i = 0; i < config_count; i++) {
const ConfigDescription& config = entry.values[i]->config;
for (size_t j = i + 1; j < config_count; j++) {
config_masks[entry_id] |=
android::util::HostToDevice32(config.diff(entry.values[j]->config));
}
}
}
type_spec_writer.Finish();
return spec_header;
}
bool FlattenTypes(BigBuffer* buffer) {
size_t expected_type_id = 1;
for (const ResourceTableTypeView& type : package_.types) {
if (type.named_type.type == ResourceType::kStyleable ||
type.named_type.type == ResourceType::kMacro) {
// Styleables and macros are not real resource types.
continue;
}
// If there is a gap in the type IDs, fill in the StringPool
// with empty values until we reach the ID we expect.
while (type.id.value() > expected_type_id) {
std::stringstream type_name;
type_name << "?" << expected_type_id;
type_pool_.MakeRef(type_name.str());
expected_type_id++;
}
expected_type_id++;
type_pool_.MakeRef(type.named_type.to_string());
const auto type_spec_header = FlattenTypeSpec(type, type.entries, buffer);
if (!type_spec_header) {
return false;
}
// Since the entries are sorted by ID, the last ID will be the largest.
const size_t num_entries = type.entries.back().id.value() + 1;
// The binary resource table lists resource entries for each
// configuration.
// We store them inverted, where a resource entry lists the values for
// each
// configuration available. Here we reverse this to match the binary
// table.
std::map<ConfigDescription, std::vector<FlatEntry>> config_to_entry_list_map;
for (const ResourceTableEntryView& entry : type.entries) {
if (entry.staged_id) {
aliases_.insert(std::make_pair(
entry.staged_id.value().id.id,
ResourceId(package_.id.value(), type.id.value(), entry.id.value()).id));
}
uint32_t local_key_index;
auto onObfuscate = [this, &local_key_index, &entry](Obfuscator::Result obfuscatedResult,
const ResourceName& resource_name) {
if (obfuscatedResult == Obfuscator::Result::Keep_ExemptionList) {
local_key_index = (uint32_t)key_pool_.MakeRef(entry.name).index();
} else if (obfuscatedResult == Obfuscator::Result::Keep_Overlayable) {
// if the resource name of the specific entry is obfuscated and this
// entry is in the overlayable list, the overlay can't work on this
// overlayable at runtime because the name has been obfuscated in
// resources.arsc during flatten operation.
const OverlayableItem& item = entry.overlayable_item.value();
context_->GetDiagnostics()->Warn(android::DiagMessage(item.overlayable->source)
<< "The resource name of overlayable entry '"
<< resource_name.to_string()
<< "' shouldn't be obfuscated in resources.arsc");
local_key_index = (uint32_t)key_pool_.MakeRef(entry.name).index();
} else {
local_key_index =
(uint32_t)key_pool_.MakeRef(Obfuscator::kObfuscatedResourceName).index();
}
};
Obfuscator::ObfuscateResourceName(collapse_key_stringpool_, name_collapse_exemptions_,
type.named_type, entry, onObfuscate);
// Group values by configuration.
for (auto& config_value : entry.values) {
config_to_entry_list_map[config_value->config].push_back(
FlatEntry{&entry, config_value->value.get(), local_key_index});
}
}
// Flatten a configuration value.
for (auto& entry : config_to_entry_list_map) {
if (!FlattenConfig(type, entry.first, num_entries, &entry.second, buffer)) {
return false;
}
}
// And now we can update the type entries count in the typeSpec header.
type_spec_header->typesCount = android::util::HostToDevice16(uint16_t(std::min<uint32_t>(
config_to_entry_list_map.size(), std::numeric_limits<uint16_t>::max())));
}
return true;
}
void FlattenLibrarySpec(BigBuffer* buffer) {
ChunkWriter lib_writer(buffer);
ResTable_lib_header* lib_header =
lib_writer.StartChunk<ResTable_lib_header>(RES_TABLE_LIBRARY_TYPE);
const size_t num_entries = (package_.id.value() == 0x00 ? 1 : 0) + shared_libs_->size();
CHECK(num_entries > 0);
lib_header->count = android::util::HostToDevice32(num_entries);
ResTable_lib_entry* lib_entry = buffer->NextBlock<ResTable_lib_entry>(num_entries);
if (package_.id.value() == 0x00) {
// Add this package
lib_entry->packageId = android::util::HostToDevice32(0x00);
strcpy16_htod(lib_entry->packageName, arraysize(lib_entry->packageName),
android::util::Utf8ToUtf16(package_.name));
++lib_entry;
}
for (auto& map_entry : *shared_libs_) {
lib_entry->packageId = android::util::HostToDevice32(map_entry.first);
strcpy16_htod(lib_entry->packageName, arraysize(lib_entry->packageName),
android::util::Utf8ToUtf16(map_entry.second));
++lib_entry;
}
lib_writer.Finish();
}
IAaptContext* context_;
android::IDiagnostics* diag_;
const ResourceTablePackageView package_;
const ResourceTable::ReferencedPackages* shared_libs_;
SparseEntriesMode sparse_entries_;
bool compact_entries_;
android::StringPool type_pool_;
android::StringPool key_pool_;
bool collapse_key_stringpool_;
const std::set<ResourceName>& name_collapse_exemptions_;
std::map<uint32_t, uint32_t> aliases_;
bool deduplicate_entry_values_;
};
} // namespace
bool TableFlattener::Consume(IAaptContext* context, ResourceTable* table) {
TRACE_CALL();
// We must do this before writing the resources, since the string pool IDs may change.
table->string_pool.Prune();
table->string_pool.Sort(
[](const android::StringPool::Context& a, const android::StringPool::Context& b) -> int {
int diff = util::compare(a.priority, b.priority);
if (diff == 0) {
diff = a.config.compare(b.config);
}
return diff;
});
// Write the ResTable header.
const auto& table_view =
table->GetPartitionedView(ResourceTableViewOptions{.create_alias_entries = true});
ChunkWriter table_writer(buffer_);
ResTable_header* table_header = table_writer.StartChunk<ResTable_header>(RES_TABLE_TYPE);
table_header->packageCount = android::util::HostToDevice32(table_view.packages.size());
// Flatten the values string pool.
android::StringPool::FlattenUtf8(table_writer.buffer(), table->string_pool,
context->GetDiagnostics());
android::BigBuffer package_buffer(1024);
// Flatten each package.
for (auto& package : table_view.packages) {
if (context->GetPackageType() == PackageType::kApp) {
// Write a self mapping entry for this package if the ID is non-standard (0x7f).
CHECK((bool)package.id) << "Resource ids have not been assigned before flattening the table";
const uint8_t package_id = package.id.value();
if (package_id != kFrameworkPackageId && package_id != kAppPackageId) {
auto result = table->included_packages_.insert({package_id, package.name});
if (!result.second && result.first->second != package.name) {
// A mapping for this package ID already exists, and is a different package. Error!
context->GetDiagnostics()->Error(
android::DiagMessage() << android::base::StringPrintf(
"can't map package ID %02x to '%s'. Already mapped to '%s'", package_id,
package.name.c_str(), result.first->second.c_str()));
return false;
}
}
}
PackageFlattener flattener(context, package, &table->included_packages_,
options_.sparse_entries,
options_.use_compact_entries,
options_.collapse_key_stringpool,
options_.name_collapse_exemptions,
options_.deduplicate_entry_values);
if (!flattener.FlattenPackage(&package_buffer)) {
return false;
}
}
// Finally merge all the packages into the main buffer.
table_writer.buffer()->AppendBuffer(std::move(package_buffer));
table_writer.Finish();
return true;
}
} // namespace aapt