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- // Copyright 2016 The Chromium Authors. All rights reserved.
- // Use of this source code is governed by a BSD-style license that can be
- // found in the LICENSE file.
- #include "courgette/disassembler_win32.h"
- #include <algorithm>
- #include "base/bind.h"
- #include "base/logging.h"
- #include "courgette/assembly_program.h"
- #include "courgette/courgette.h"
- #if COURGETTE_HISTOGRAM_TARGETS
- #include <iostream>
- #endif
- namespace courgette {
- DisassemblerWin32::DisassemblerWin32(const uint8_t* start, size_t length)
- : Disassembler(start, length) {}
- RVA DisassemblerWin32::FileOffsetToRVA(FileOffset file_offset) const {
- for (int i = 0; i < number_of_sections_; ++i) {
- const Section* section = §ions_[i];
- if (file_offset >= section->file_offset_of_raw_data) {
- FileOffset offset_in_section =
- file_offset - section->file_offset_of_raw_data;
- if (offset_in_section < section->size_of_raw_data)
- return static_cast<RVA>(section->virtual_address + offset_in_section);
- }
- }
- NOTREACHED();
- return kNoRVA;
- }
- FileOffset DisassemblerWin32::RVAToFileOffset(RVA rva) const {
- const Section* section = RVAToSection(rva);
- if (section != nullptr) {
- FileOffset offset_in_section = rva - section->virtual_address;
- // Need this extra check, since an |rva| may be valid for a section, but is
- // non-existent in an image (e.g. uninit data).
- if (offset_in_section >= section->size_of_raw_data)
- return kNoFileOffset;
- return static_cast<FileOffset>(section->file_offset_of_raw_data +
- offset_in_section);
- }
- // Small RVA values point into the file header in the loaded image.
- // RVA 0 is the module load address which Windows uses as the module handle.
- // RVA 2 sometimes occurs, I'm not sure what it is, but it would map into the
- // DOS header.
- if (rva == 0 || rva == 2)
- return static_cast<FileOffset>(rva);
- NOTREACHED();
- return kNoFileOffset;
- }
- // ParseHeader attempts to match up the buffer with the Windows data
- // structures that exist within a Windows 'Portable Executable' format file.
- // Returns 'true' if the buffer matches, and 'false' if the data looks
- // suspicious. Rather than try to 'map' the buffer to the numerous windows
- // structures, we extract the information we need into the courgette::PEInfo
- // structure.
- //
- bool DisassemblerWin32::ParseHeader() {
- if (!IsRangeInBounds(kOffsetOfFileAddressOfNewExeHeader, 4))
- return Bad("Too small");
- // Have 'MZ' magic for a DOS header?
- if (start()[0] != 'M' || start()[1] != 'Z')
- return Bad("Not MZ");
- // offset from DOS header to PE header is stored in DOS header.
- FileOffset pe_header_offset = static_cast<FileOffset>(
- ReadU32(start(), kOffsetOfFileAddressOfNewExeHeader));
- if (pe_header_offset % 8 != 0)
- return Bad("Misaligned PE header");
- if (pe_header_offset < kOffsetOfFileAddressOfNewExeHeader + 4)
- return Bad("PE header pathological overlap");
- if (!IsRangeInBounds(pe_header_offset, kMinPeHeaderSize))
- return Bad("PE header past end of file");
- const uint8_t* const pe_header = FileOffsetToPointer(pe_header_offset);
- // The 'PE' header is an IMAGE_NT_HEADERS structure as defined in WINNT.H.
- // See http://msdn.microsoft.com/en-us/library/ms680336(VS.85).aspx
- //
- // The first field of the IMAGE_NT_HEADERS is the signature.
- if (!(pe_header[0] == 'P' && pe_header[1] == 'E' && pe_header[2] == 0 &&
- pe_header[3] == 0)) {
- return Bad("No PE signature");
- }
- // The second field of the IMAGE_NT_HEADERS is the COFF header.
- // The COFF header is also called an IMAGE_FILE_HEADER
- // http://msdn.microsoft.com/en-us/library/ms680313(VS.85).aspx
- FileOffset coff_header_offset = pe_header_offset + 4;
- if (!IsRangeInBounds(coff_header_offset, kSizeOfCoffHeader))
- return Bad("COFF header past end of file");
- const uint8_t* const coff_header = start() + coff_header_offset;
- machine_type_ = ReadU16(coff_header, 0);
- number_of_sections_ = ReadU16(coff_header, 2);
- size_of_optional_header_ = ReadU16(coff_header, 16);
- // Check we can read the magic.
- if (size_of_optional_header_ < 2)
- return Bad("Optional header no magic");
- // Check that we can read the rest of the the fixed fields. Data directories
- // directly follow the fixed fields of the IMAGE_OPTIONAL_HEADER.
- if (size_of_optional_header_ < RelativeOffsetOfDataDirectories())
- return Bad("Optional header too short");
- // The rest of the IMAGE_NT_HEADERS is the IMAGE_OPTIONAL_HEADER(32|64)
- FileOffset optional_header_offset = pe_header_offset + kMinPeHeaderSize;
- if (!IsRangeInBounds(optional_header_offset, size_of_optional_header_))
- return Bad("Optional header past end of file");
- optional_header_ = start() + optional_header_offset;
- uint16_t magic = ReadU16(optional_header_, 0);
- switch (kind()) {
- case EXE_WIN_32_X86:
- if (magic != kImageNtOptionalHdr32Magic)
- return Bad("64 bit executables are not supported by this disassembler");
- break;
- case EXE_WIN_32_X64:
- if (magic != kImageNtOptionalHdr64Magic)
- return Bad("32 bit executables are not supported by this disassembler");
- break;
- default:
- return Bad("Unrecognized magic");
- }
- // The optional header is either an IMAGE_OPTIONAL_HEADER32 or
- // IMAGE_OPTIONAL_HEADER64
- // http://msdn.microsoft.com/en-us/library/ms680339(VS.85).aspx
- //
- // Copy the fields we care about.
- size_of_code_ = ReadU32(optional_header_, 4);
- size_of_initialized_data_ = ReadU32(optional_header_, 8);
- size_of_uninitialized_data_ = ReadU32(optional_header_, 12);
- base_of_code_ = ReadU32(optional_header_, 20);
- switch (kind()) {
- case EXE_WIN_32_X86:
- base_of_data_ = ReadU32(optional_header_, 24);
- image_base_ = ReadU32(optional_header_, 28);
- size_of_image_ = ReadU32(optional_header_, 56);
- number_of_data_directories_ = ReadU32(optional_header_, 92);
- break;
- case EXE_WIN_32_X64:
- base_of_data_ = 0;
- image_base_ = ReadU64(optional_header_, 24);
- size_of_image_ = ReadU32(optional_header_, 56);
- number_of_data_directories_ = ReadU32(optional_header_, 108);
- break;
- default:
- NOTREACHED();
- }
- if (size_of_image_ >= 0x80000000U)
- return Bad("Invalid SizeOfImage");
- if (size_of_code_ >= length() || size_of_initialized_data_ >= length() ||
- size_of_code_ + size_of_initialized_data_ >= length()) {
- // This validation fires on some perfectly fine executables.
- // return Bad("code or initialized data too big");
- }
- // TODO(sra): we can probably get rid of most of the data directories.
- bool b = true;
- // 'b &= ...' could be short circuit 'b = b && ...' but it is not necessary
- // for correctness and it compiles smaller this way.
- b &= ReadDataDirectory(0, &export_table_);
- b &= ReadDataDirectory(1, &import_table_);
- b &= ReadDataDirectory(2, &resource_table_);
- b &= ReadDataDirectory(3, &exception_table_);
- b &= ReadDataDirectory(5, &base_relocation_table_);
- b &= ReadDataDirectory(11, &bound_import_table_);
- b &= ReadDataDirectory(12, &import_address_table_);
- b &= ReadDataDirectory(13, &delay_import_descriptor_);
- b &= ReadDataDirectory(14, &clr_runtime_header_);
- if (!b)
- return Bad("Malformed data directory");
- // Sections follow the optional header.
- FileOffset sections_offset =
- optional_header_offset + size_of_optional_header_;
- if (!IsArrayInBounds(sections_offset, number_of_sections_, sizeof(Section)))
- return Bad("Sections past end of file");
- sections_ = reinterpret_cast<const Section*>(start() + sections_offset);
- if (!CheckSectionRanges())
- return Bad("Out of bound section");
- size_t detected_length = 0;
- for (int i = 0; i < number_of_sections_; ++i) {
- const Section* section = §ions_[i];
- // TODO(sra): consider using the 'characteristics' field of the section
- // header to see if the section contains instructions.
- if (memcmp(section->name, ".text", 6) == 0)
- has_text_section_ = true;
- uint32_t section_end =
- section->file_offset_of_raw_data + section->size_of_raw_data;
- if (section_end > detected_length)
- detected_length = section_end;
- }
- // Pretend our in-memory copy is only as long as our detected length.
- ReduceLength(detected_length);
- if (!has_text_section()) {
- return Bad("Resource-only executables are not yet supported");
- }
- return Good();
- }
- ////////////////////////////////////////////////////////////////////////////////
- bool DisassemblerWin32::ParseRelocs(std::vector<RVA>* relocs) {
- relocs->clear();
- size_t relocs_size = base_relocation_table_.size_;
- if (relocs_size == 0)
- return true;
- // The format of the base relocation table is a sequence of variable sized
- // IMAGE_BASE_RELOCATION blocks. Search for
- // "The format of the base relocation data is somewhat quirky"
- // at http://msdn.microsoft.com/en-us/library/ms809762.aspx
- const uint8_t* relocs_start = RVAToPointer(base_relocation_table_.address_);
- if (relocs_start == nullptr || relocs_start < start() ||
- relocs_start >= end())
- return Bad(".relocs outside image");
- // Make sure entire base relocation table is within the buffer.
- if (relocs_size > static_cast<size_t>(end() - relocs_start))
- return Bad(".relocs outside image");
- const uint8_t* relocs_end = relocs_start + relocs_size;
- const uint8_t* block = relocs_start;
- // Walk the variable sized blocks.
- while (block + 8 < relocs_end) {
- RVA page_rva = ReadU32(block, 0);
- uint32_t size = ReadU32(block, 4);
- if (size < 8 || // Size includes header ...
- size % 4 != 0) // ... and is word aligned.
- return Bad("Unreasonable relocs block");
- const uint8_t* end_entries = block + size;
- if (end_entries <= block || end_entries <= start() || end_entries > end())
- return Bad(".relocs block outside image");
- // Walk through the two-byte entries.
- for (const uint8_t* p = block + 8; p < end_entries; p += 2) {
- uint16_t entry = ReadU16(p, 0);
- int type = entry >> 12;
- int offset = entry & 0xFFF;
- RVA rva = page_rva + offset;
- // Skip the relocs that live outside of the image. It might be the case
- // if a reloc is relative to a register, e.g.:
- // mov ecx,dword ptr [eax+044D5888h]
- RVA target_rva = PointerToTargetRVA(RVAToPointer(rva));
- if (target_rva == kNoRVA) {
- continue;
- }
- if (SupportsRelTableType(type)) {
- relocs->push_back(rva);
- } else if (type == 0) { // IMAGE_REL_BASED_ABSOLUTE
- // Ignore, used as padding.
- } else {
- // Does not occur in Windows x86/x64 executables.
- return Bad("Unknown type of reloc");
- }
- }
- block += size;
- }
- std::sort(relocs->begin(), relocs->end());
- DCHECK(relocs->empty() || relocs->back() != kUnassignedRVA);
- return true;
- }
- const Section* DisassemblerWin32::RVAToSection(RVA rva) const {
- for (int i = 0; i < number_of_sections_; ++i) {
- const Section* section = §ions_[i];
- if (rva >= section->virtual_address) {
- FileOffset offset_in_section = rva - section->virtual_address;
- if (offset_in_section < section->virtual_size)
- return section;
- }
- }
- return nullptr;
- }
- std::string DisassemblerWin32::SectionName(const Section* section) {
- if (section == nullptr)
- return "<none>";
- char name[9];
- memcpy(name, section->name, 8);
- name[8] = '\0'; // Ensure termination.
- return name;
- }
- // static
- bool DisassemblerWin32::QuickDetect(const uint8_t* start,
- size_t length,
- uint16_t magic) {
- if (length < kOffsetOfFileAddressOfNewExeHeader + 4)
- return false;
- // Have 'MZ' magic for a DOS header?
- if (start[0] != 'M' || start[1] != 'Z')
- return false;
- FileOffset pe_header_offset = static_cast<FileOffset>(
- ReadU32(start, kOffsetOfFileAddressOfNewExeHeader));
- if (pe_header_offset % 8 != 0 ||
- pe_header_offset < kOffsetOfFileAddressOfNewExeHeader + 4 ||
- pe_header_offset >= length ||
- length - pe_header_offset < kMinPeHeaderSize) {
- return false;
- }
- const uint8_t* pe_header = start + pe_header_offset;
- if (!(pe_header[0] == 'P' && pe_header[1] == 'E' && pe_header[2] == 0 &&
- pe_header[3] == 0)) {
- return false;
- }
- FileOffset optional_header_offset = pe_header_offset + kMinPeHeaderSize;
- if (optional_header_offset >= length || length - optional_header_offset < 2)
- return false;
- const uint8_t* optional_header = start + optional_header_offset;
- return magic == ReadU16(optional_header, 0);
- }
- bool DisassemblerWin32::IsRvaRangeInBounds(size_t start, size_t length) {
- return start < size_of_image_ && length <= size_of_image_ - start;
- }
- bool DisassemblerWin32::CheckSectionRanges() {
- for (int i = 0; i < number_of_sections_; ++i) {
- const Section* section = §ions_[i];
- if (!IsRangeInBounds(section->file_offset_of_raw_data,
- section->size_of_raw_data) ||
- !IsRvaRangeInBounds(section->virtual_address, section->virtual_size)) {
- return false;
- }
- }
- return true;
- }
- bool DisassemblerWin32::ExtractAbs32Locations() {
- abs32_locations_.clear();
- if (!ParseRelocs(&abs32_locations_))
- return false;
- #if COURGETTE_HISTOGRAM_TARGETS
- for (size_t i = 0; i < abs32_locations_.size(); ++i) {
- RVA rva = abs32_locations_[i];
- // The 4 bytes at the relocation are a reference to some address.
- ++abs32_target_rvas_[PointerToTargetRVA(RVAToPointer(rva))];
- }
- #endif
- return true;
- }
- bool DisassemblerWin32::ExtractRel32Locations() {
- FileOffset file_offset = 0;
- while (file_offset < length()) {
- const Section* section = FindNextSection(file_offset);
- if (section == nullptr)
- break;
- if (file_offset < section->file_offset_of_raw_data)
- file_offset = section->file_offset_of_raw_data;
- ParseRel32RelocsFromSection(section);
- file_offset += section->size_of_raw_data;
- }
- std::sort(rel32_locations_.begin(), rel32_locations_.end());
- DCHECK(rel32_locations_.empty() || rel32_locations_.back() != kUnassignedRVA);
- #if COURGETTE_HISTOGRAM_TARGETS
- VLOG(1) << "abs32_locations_ " << abs32_locations_.size()
- << "\nrel32_locations_ " << rel32_locations_.size()
- << "\nabs32_target_rvas_ " << abs32_target_rvas_.size()
- << "\nrel32_target_rvas_ " << rel32_target_rvas_.size();
- int common = 0;
- std::map<RVA, int>::iterator abs32_iter = abs32_target_rvas_.begin();
- std::map<RVA, int>::iterator rel32_iter = rel32_target_rvas_.begin();
- while (abs32_iter != abs32_target_rvas_.end() &&
- rel32_iter != rel32_target_rvas_.end()) {
- if (abs32_iter->first < rel32_iter->first) {
- ++abs32_iter;
- } else if (rel32_iter->first < abs32_iter->first) {
- ++rel32_iter;
- } else {
- ++common;
- ++abs32_iter;
- ++rel32_iter;
- }
- }
- VLOG(1) << "common " << common;
- #endif
- return true;
- }
- RvaVisitor* DisassemblerWin32::CreateAbs32TargetRvaVisitor() {
- return new RvaVisitor_Abs32(abs32_locations_, *this);
- }
- RvaVisitor* DisassemblerWin32::CreateRel32TargetRvaVisitor() {
- return new RvaVisitor_Rel32(rel32_locations_, *this);
- }
- void DisassemblerWin32::RemoveUnusedRel32Locations(
- AssemblyProgram* program) {
- auto cond = [this, program](RVA rva) -> bool {
- // + 4 since offset is relative to start of next instruction.
- RVA target_rva = rva + 4 + Read32LittleEndian(RVAToPointer(rva));
- return program->FindRel32Label(target_rva) == nullptr;
- };
- rel32_locations_.erase(
- std::remove_if(rel32_locations_.begin(), rel32_locations_.end(), cond),
- rel32_locations_.end());
- }
- InstructionGenerator DisassemblerWin32::GetInstructionGenerator(
- AssemblyProgram* program) {
- return base::BindRepeating(&DisassemblerWin32::ParseFile,
- base::Unretained(this), program);
- }
- CheckBool DisassemblerWin32::ParseFile(AssemblyProgram* program,
- InstructionReceptor* receptor) const {
- // Walk all the bytes in the file, whether or not in a section.
- FileOffset file_offset = 0;
- while (file_offset < length()) {
- const Section* section = FindNextSection(file_offset);
- if (section == nullptr) {
- // No more sections. There should not be extra stuff following last
- // section.
- // ParseNonSectionFileRegion(file_offset, pe_info().length(), receptor);
- break;
- }
- if (file_offset < section->file_offset_of_raw_data) {
- FileOffset section_start_offset = section->file_offset_of_raw_data;
- if (!ParseNonSectionFileRegion(file_offset, section_start_offset,
- receptor)) {
- return false;
- }
- file_offset = section_start_offset;
- }
- FileOffset end = file_offset + section->size_of_raw_data;
- if (!ParseFileRegion(section, file_offset, end, program, receptor))
- return false;
- file_offset = end;
- }
- #if COURGETTE_HISTOGRAM_TARGETS
- HistogramTargets("abs32 relocs", abs32_target_rvas_);
- HistogramTargets("rel32 relocs", rel32_target_rvas_);
- #endif
- return true;
- }
- CheckBool DisassemblerWin32::ParseNonSectionFileRegion(
- FileOffset start_file_offset,
- FileOffset end_file_offset,
- InstructionReceptor* receptor) const {
- if (incomplete_disassembly_)
- return true;
- if (end_file_offset > start_file_offset) {
- if (!receptor->EmitMultipleBytes(FileOffsetToPointer(start_file_offset),
- end_file_offset - start_file_offset)) {
- return false;
- }
- }
- return true;
- }
- CheckBool DisassemblerWin32::ParseFileRegion(
- const Section* section,
- FileOffset start_file_offset,
- FileOffset end_file_offset,
- AssemblyProgram* program,
- InstructionReceptor* receptor) const {
- RVA relocs_start_rva = base_relocation_table().address_;
- const uint8_t* start_pointer = FileOffsetToPointer(start_file_offset);
- const uint8_t* end_pointer = FileOffsetToPointer(end_file_offset);
- RVA start_rva = FileOffsetToRVA(start_file_offset);
- RVA end_rva = start_rva + section->virtual_size;
- const int kVAWidth = AbsVAWidth();
- // Quick way to convert from Pointer to RVA within a single Section is to
- // subtract 'pointer_to_rva'.
- const uint8_t* const adjust_pointer_to_rva = start_pointer - start_rva;
- std::vector<RVA>::const_iterator rel32_pos = rel32_locations_.begin();
- std::vector<RVA>::const_iterator abs32_pos = abs32_locations_.begin();
- if (!receptor->EmitOrigin(start_rva))
- return false;
- const uint8_t* p = start_pointer;
- while (p < end_pointer) {
- RVA current_rva = static_cast<RVA>(p - adjust_pointer_to_rva);
- // The base relocation table is usually in the .relocs section, but it could
- // actually be anywhere. Make sure we skip it because we will regenerate it
- // during assembly.
- if (current_rva == relocs_start_rva) {
- if (!receptor->EmitPeRelocs())
- return false;
- uint32_t relocs_size = base_relocation_table().size_;
- if (relocs_size) {
- p += relocs_size;
- continue;
- }
- }
- while (abs32_pos != abs32_locations_.end() && *abs32_pos < current_rva)
- ++abs32_pos;
- if (abs32_pos != abs32_locations_.end() && *abs32_pos == current_rva) {
- RVA target_rva = PointerToTargetRVA(p);
- DCHECK_NE(kNoRVA, target_rva);
- // TODO(sra): target could be Label+offset. It is not clear how to guess
- // which it might be. We assume offset==0.
- Label* label = program->FindAbs32Label(target_rva);
- DCHECK(label);
- if (!EmitAbs(label, receptor))
- return false;
- p += kVAWidth;
- continue;
- }
- while (rel32_pos != rel32_locations_.end() && *rel32_pos < current_rva)
- ++rel32_pos;
- if (rel32_pos != rel32_locations_.end() && *rel32_pos == current_rva) {
- // + 4 since offset is relative to start of next instruction.
- RVA target_rva = current_rva + 4 + Read32LittleEndian(p);
- Label* label = program->FindRel32Label(target_rva);
- DCHECK(label);
- if (!receptor->EmitRel32(label))
- return false;
- p += 4;
- continue;
- }
- if (incomplete_disassembly_) {
- if ((abs32_pos == abs32_locations_.end() || end_rva <= *abs32_pos) &&
- (rel32_pos == rel32_locations_.end() || end_rva <= *rel32_pos) &&
- (end_rva <= relocs_start_rva || current_rva >= relocs_start_rva)) {
- // No more relocs in this section, don't bother encoding bytes.
- break;
- }
- }
- if (!receptor->EmitSingleByte(*p))
- return false;
- p += 1;
- }
- return true;
- }
- #if COURGETTE_HISTOGRAM_TARGETS
- // Histogram is printed to std::cout. It is purely for debugging the algorithm
- // and is only enabled manually in 'exploration' builds. I don't want to add
- // command-line configuration for this feature because this code has to be
- // small, which means compiled-out.
- void DisassemblerWin32::HistogramTargets(const char* kind,
- const std::map<RVA, int>& map) const {
- int total = 0;
- std::map<int, std::vector<RVA>> h;
- for (std::map<RVA, int>::const_iterator p = map.begin(); p != map.end();
- ++p) {
- h[p->second].push_back(p->first);
- total += p->second;
- }
- std::cout << total << " " << kind << " to " << map.size() << " unique targets"
- << std::endl;
- std::cout << "indegree: #targets-with-indegree (example)" << std::endl;
- const int kFirstN = 15;
- bool someSkipped = false;
- int index = 0;
- for (std::map<int, std::vector<RVA>>::reverse_iterator p = h.rbegin();
- p != h.rend(); ++p) {
- ++index;
- if (index <= kFirstN || p->first <= 3) {
- if (someSkipped) {
- std::cout << "..." << std::endl;
- }
- size_t count = p->second.size();
- std::cout << std::dec << p->first << ": " << count;
- if (count <= 2) {
- for (size_t i = 0; i < count; ++i)
- std::cout << " " << DescribeRVA(p->second[i]);
- }
- std::cout << std::endl;
- someSkipped = false;
- } else {
- someSkipped = true;
- }
- }
- }
- #endif // COURGETTE_HISTOGRAM_TARGETS
- // DescribeRVA is for debugging only. I would put it under #ifdef DEBUG except
- // that during development I'm finding I need to call it when compiled in
- // Release mode. Hence:
- // TODO(sra): make this compile only for debug mode.
- std::string DisassemblerWin32::DescribeRVA(RVA rva) const {
- const Section* section = RVAToSection(rva);
- std::ostringstream s;
- s << std::hex << rva;
- if (section) {
- s << " (";
- s << SectionName(section) << "+" << std::hex
- << (rva - section->virtual_address) << ")";
- }
- return s.str();
- }
- const Section* DisassemblerWin32::FindNextSection(
- FileOffset file_offset) const {
- const Section* best = nullptr;
- for (int i = 0; i < number_of_sections_; ++i) {
- const Section* section = §ions_[i];
- if (section->size_of_raw_data > 0) { // i.e. has data in file.
- if (file_offset <= section->file_offset_of_raw_data) {
- if (best == nullptr ||
- section->file_offset_of_raw_data < best->file_offset_of_raw_data) {
- best = section;
- }
- }
- }
- }
- return best;
- }
- bool DisassemblerWin32::ReadDataDirectory(int index,
- ImageDataDirectory* directory) {
- if (index < number_of_data_directories_) {
- FileOffset file_offset = index * 8 + RelativeOffsetOfDataDirectories();
- if (file_offset >= size_of_optional_header_)
- return Bad("Number of data directories inconsistent");
- const uint8_t* data_directory = optional_header_ + file_offset;
- if (data_directory < start() || data_directory + 8 >= end())
- return Bad("Data directory outside image");
- RVA rva = ReadU32(data_directory, 0);
- size_t size = ReadU32(data_directory, 4);
- if (size > size_of_image_)
- return Bad("Data directory size too big");
- // TODO(sra): validate RVA.
- directory->address_ = rva;
- directory->size_ = static_cast<uint32_t>(size);
- return true;
- } else {
- directory->address_ = 0;
- directory->size_ = 0;
- return true;
- }
- }
- } // namespace courgette
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