void HandleLongOrUnprintableString(std::wstring const& name,
std::wstring const& description,
std::size_t tabs,
WarningType warning_type,
std::string value)
{
std::wostream& out = GetOutputStreamW();
// TODO: Fix perf for extremely long names. Instead of reading indefinitely
// and then checking the size after the fact, we should perform a bounded
// read.
auto const unprintable = FindFirstUnprintableClassicLocale(value);
std::size_t const kMaxNameLength = 1024;
if (unprintable != std::string::npos)
{
WriteNormal(out,
L"WARNING! Detected unprintable " + description +
L". Truncating.",
tabs);
WarnForCurrentFile(warning_type);
value.erase(unprintable);
}
else if (value.size() > kMaxNameLength)
{
WriteNormal(out,
L"WARNING! Detected suspiciously long " + description +
L". Truncating.",
tabs);
WarnForCurrentFile(warning_type);
value.erase(kMaxNameLength);
}
WriteNamedNormal(out, name, value.c_str(), tabs);
}
void HandleLongOrUnprintableString(std::wstring const& name,
std::wstring const& description,
std::size_t tabs,
WarningType warning_type,
std::string value)
{
std::wostream& out = std::wcout;
auto const unprintable = FindFirstUnprintableClassicLocale(value);
std::size_t const kMaxNameLength = 1024;
if (unprintable != std::string::npos)
{
WriteNormal(out,
L"WARNING! Detected unprintable " + description +
L". Truncating.",
tabs);
WarnForCurrentFile(warning_type);
value.erase(unprintable);
}
else if (value.size() > kMaxNameLength)
{
WriteNormal(out,
L"WARNING! Detected suspiciously long " + description +
L". Truncating.",
tabs);
WarnForCurrentFile(warning_type);
value.erase(kMaxNameLength);
}
WriteNamedNormal(out, name, value.c_str(), tabs);
}
void DisassembleEp(hadesmem::Process const& process,
hadesmem::PeFile const& pe_file,
std::uintptr_t ep_rva,
void* ep_va,
std::size_t tabs)
{
if (!ep_va)
{
return;
}
std::wostream& out = GetOutputStreamW();
// Get the number of bytes from the EP to the end of the file.
std::size_t max_buffer_size = GetBytesToEndOfFile(pe_file, ep_va);
// Clamp the amount of data read to the theoretical maximum.
std::size_t const kMaxInstructions = 10U;
std::size_t const kMaxInstructionLen = 15U;
std::size_t const kMaxInstructionsBytes =
kMaxInstructions * kMaxInstructionLen;
max_buffer_size = (std::min)(max_buffer_size, kMaxInstructionsBytes);
auto const disasm_buf =
hadesmem::ReadVector<std::uint8_t>(process, ep_va, max_buffer_size);
std::uint64_t const ip = hadesmem::GetRuntimeBase(process, pe_file) + ep_rva;
ud_t ud_obj;
ud_init(&ud_obj);
ud_set_input_buffer(&ud_obj, disasm_buf.data(), max_buffer_size);
ud_set_syntax(&ud_obj, UD_SYN_INTEL);
ud_set_pc(&ud_obj, ip);
ud_set_mode(&ud_obj, pe_file.Is64() ? 64 : 32);
// Be pessimistic. Use the minimum theoretical amount of instrutions we could
// fit in our buffer.
std::size_t const instruction_count = max_buffer_size / kMaxInstructionLen;
for (std::size_t i = 0U; i < instruction_count; ++i)
{
std::uint32_t const len = ud_disassemble(&ud_obj);
if (len == 0)
{
WriteNormal(out, L"WARNING! Disassembly failed.", tabs);
// If we can't disassemble at least 5 instructions there's probably
// something strange about the function. Even in the case of a nullsub
// there is typically some INT3 or NOP padding after it...
WarnForCurrentFile(i < 5U ? WarningType::kUnsupported
: WarningType::kSuspicious);
break;
}
char const* const asm_str = ud_insn_asm(&ud_obj);
HADESMEM_DETAIL_ASSERT(asm_str);
char const* const asm_bytes_str = ud_insn_hex(&ud_obj);
HADESMEM_DETAIL_ASSERT(asm_bytes_str);
auto const diasm_line =
hadesmem::detail::MultiByteToWideChar(asm_str) + L" (" +
hadesmem::detail::MultiByteToWideChar(asm_bytes_str) + L")";
WriteNormal(out, diasm_line, tabs);
}
}
void DumpSections(hadesmem::Process const& process,
hadesmem::PeFile const& pe_file)
{
hadesmem::SectionList sections(process, pe_file);
std::wostream& out = GetOutputStreamW();
if (std::begin(sections) != std::end(sections))
{
WriteNewline(out);
WriteNormal(out, L"Sections:", 1);
}
else
{
// Other checks on number of sections are done as part of header handling.
hadesmem::NtHeaders const nt_hdrs(process, pe_file);
if (nt_hdrs.GetNumberOfSections())
{
WriteNewline(out);
WriteNormal(out, L"WARNING! Section list is inavlid.", 1);
WarnForCurrentFile(WarningType::kUnsupported);
}
}
for (auto const& s : sections)
{
WriteNewline(out);
if (s.IsVirtual())
{
WriteNormal(out, L"WARNING! Section is virtual.", 2);
WarnForCurrentFile(WarningType::kSuspicious);
}
HandleLongOrUnprintableString(
L"name", L"section name", 2, WarningType::kSuspicious, s.GetName());
WriteNamedHex(out, L"VirtualAddress", s.GetVirtualAddress(), 2);
WriteNamedHex(out, L"VirtualSize", s.GetVirtualSize(), 2);
WriteNamedHex(out, L"PointerToRawData", s.GetPointerToRawData(), 2);
WriteNamedHex(out, L"SizeOfRawData", s.GetSizeOfRawData(), 2);
WriteNamedHex(out, L"PointerToRelocations", s.GetPointerToRelocations(), 2);
WriteNamedHex(out, L"PointerToLinenumbers", s.GetPointerToLinenumbers(), 2);
WriteNamedHex(out, L"NumberOfRelocations", s.GetNumberOfRelocations(), 2);
WriteNamedHex(out, L"NumberOfLinenumbers", s.GetNumberOfLinenumbers(), 2);
WriteNamedHex(out, L"Characteristics", s.GetCharacteristics(), 2);
}
}
void DumpTls(hadesmem::Process const& process, hadesmem::PeFile const& pe_file)
{
std::unique_ptr<hadesmem::TlsDir const> tls_dir;
try
{
tls_dir = std::make_unique<hadesmem::TlsDir>(process, pe_file);
}
catch (std::exception const& /*e*/)
{
return;
}
std::wostream& out = GetOutputStreamW();
WriteNewline(out);
WriteNormal(out, L"TLS:", 1);
WriteNewline(out);
WriteNamedHex(
out, L"StartAddressOfRawData", tls_dir->GetStartAddressOfRawData(), 2);
WriteNamedHex(
out, L"EndAddressOfRawData", tls_dir->GetEndAddressOfRawData(), 2);
WriteNamedHex(out, L"AddressOfIndex", tls_dir->GetAddressOfIndex(), 2);
WriteNamedHex(
out, L"AddressOfCallBacks", tls_dir->GetAddressOfCallBacks(), 2);
if (tls_dir->GetAddressOfCallBacks())
{
std::vector<ULONGLONG> callbacks;
try
{
tls_dir->GetCallbacks(std::back_inserter(callbacks));
}
catch (std::exception const& /*e*/)
{
WriteNormal(out, L"WARNING! TLS callbacks are inavlid.", 2);
WarnForCurrentFile(WarningType::kSuspicious);
}
for (auto const& c : callbacks)
{
WriteNamedHex(out, L"Callback", static_cast<DWORD_PTR>(c), 2);
}
}
WriteNamedHex(out, L"SizeOfZeroFill", tls_dir->GetSizeOfZeroFill(), 2);
WriteNamedHex(out, L"Characteristics", tls_dir->GetCharacteristics(), 2);
}
void DumpPeFile(hadesmem::Process const& process,
hadesmem::PeFile const& pe_file,
std::wstring const& path)
{
std::wostream& out = std::wcout;
ClearWarnForCurrentFile();
std::uint32_t const k1MB = (1U << 20);
std::uint32_t const k100MB = k1MB * 100;
if (pe_file.GetSize() > k100MB)
{
// Not actually unsupported, just want to flag large files.
WriteNewline(out);
WriteNormal(out, L"WARNING! File is over 100MB.", 0);
WarnForCurrentFile(WarningType::kUnsupported);
}
DumpHeaders(process, pe_file);
DumpSections(process, pe_file);
DumpTls(process, pe_file);
DumpExports(process, pe_file);
bool has_new_bound_imports_any = false;
DumpImports(process, pe_file, has_new_bound_imports_any);
DumpBoundImports(process, pe_file, has_new_bound_imports_any);
DumpRelocations(process, pe_file);
DumpStrings(process, pe_file);
HandleWarnings(path);
}
void DumpBoundImports(hadesmem::Process const& process,
hadesmem::PeFile const& pe_file,
bool has_new_bound_imports_any)
{
std::wostream& out = GetOutputStreamW();
if (!HasBoundImportDir(process, pe_file))
{
// Sample: dllmaxvals.dll (Corkami PE Corpus)
if (has_new_bound_imports_any)
{
WriteNewline(out);
WriteNormal(
out,
L"WARNING! No bound import directory on file with an import dir "
L"indicating the presence of a bound import dir.",
1);
WarnForCurrentFile(WarningType::kSuspicious);
}
return;
}
if (!has_new_bound_imports_any)
{
WriteNewline(out);
WriteNormal(
out,
L"WARNING! Seemingly valid bound import directory on file with an "
L"import dir indicating no new bound import dir.",
1);
WarnForCurrentFile(WarningType::kSuspicious);
return;
}
hadesmem::BoundImportDescriptorList const bound_import_descs(process,
pe_file);
if (std::begin(bound_import_descs) == std::end(bound_import_descs))
{
WriteNewline(out);
WriteNormal(out, L"WARNING! Empty or invalid bound import directory.", 1);
WarnForCurrentFile(WarningType::kSuspicious);
return;
}
WriteNewline(out);
WriteNormal(out, L"Bound Import Descriptors:", 1);
std::uint32_t num_descs = 0U;
for (auto const& desc : bound_import_descs)
{
WriteNewline(out);
if (num_descs++ == 1000)
{
WriteNormal(out,
L"WARNING! Processed 1000 bound import descriptors. Stopping "
L"early to avoid resource exhaustion attacks.",
2);
WarnForCurrentFile(WarningType::kUnsupported);
break;
}
DWORD const time_date_stamp = desc.GetTimeDateStamp();
std::wstring time_date_stamp_str;
if (!ConvertTimeStamp(time_date_stamp, time_date_stamp_str))
{
WriteNormal(out, L"WARNING! Invalid timestamp.", 2);
WarnForCurrentFile(WarningType::kSuspicious);
}
WriteNamedHexSuffix(
out, L"TimeDateStamp", time_date_stamp, time_date_stamp_str, 2);
WriteNamedHex(out, L"OffsetModuleName", desc.GetOffsetModuleName(), 2);
WriteNamedNormal(out, L"ModuleName", desc.GetModuleName().c_str(), 2);
WriteNamedHex(out,
L"NumberOfModuleForwarderRefs",
desc.GetNumberOfModuleForwarderRefs(),
2);
hadesmem::BoundImportForwarderRefList const forwarder_refs(
process, pe_file, desc);
if (std::begin(forwarder_refs) != std::end(forwarder_refs))
{
WriteNewline(out);
WriteNormal(out, L"Module Forwarder Refs:", 2);
}
for (auto const& forwarder : forwarder_refs)
{
WriteNewline(out);
DWORD const fwd_time_date_stamp = forwarder.GetTimeDateStamp();
std::wstring fwd_time_date_stamp_str;
if (!ConvertTimeStamp(fwd_time_date_stamp, fwd_time_date_stamp_str))
{
WriteNormal(out, L"WARNING! Invalid timestamp.", 3);
WarnForCurrentFile(WarningType::kSuspicious);
}
WriteNamedHexSuffix(
out, L"TimeDateStamp", fwd_time_date_stamp, fwd_time_date_stamp_str, 3);
WriteNamedHex(
out, L"OffsetModuleName", forwarder.GetOffsetModuleName(), 3);
WriteNamedNormal(
out, L"ModuleName", forwarder.GetModuleName().c_str(), 3);
WriteNamedHex(out, L"Reserved", forwarder.GetReserved(), 3);
}
}
}
void DumpExports(hadesmem::Process const& process,
hadesmem::PeFile const& pe_file)
{
std::unique_ptr<hadesmem::ExportDir const> export_dir;
try
{
export_dir = std::make_unique<hadesmem::ExportDir const>(process, pe_file);
}
catch (std::exception const& /*e*/)
{
return;
}
std::wostream& out = std::wcout;
WriteNewline(out);
WriteNormal(out, L"Export Dir:", 1);
WriteNewline(out);
WriteNamedHex(out, L"Characteristics", export_dir->GetCharacteristics(), 2);
DWORD const time_date_stamp = export_dir->GetTimeDateStamp();
std::wstring time_date_stamp_str;
if (!ConvertTimeStamp(time_date_stamp, time_date_stamp_str))
{
WriteNormal(out, L"WARNING! Invalid timestamp.", 2);
WarnForCurrentFile(WarningType::kSuspicious);
}
WriteNamedHexSuffix(
out, L"TimeDateStamp", time_date_stamp, time_date_stamp_str, 2);
WriteNamedHex(out, L"MajorVersion", export_dir->GetMajorVersion(), 2);
WriteNamedHex(out, L"MinorVersion", export_dir->GetMinorVersion(), 2);
WriteNamedHex(out, L"Name (Raw)", export_dir->GetNameRaw(), 2);
// Name is not guaranteed to be valid.
// Sample: dllord.dll (Corkami PE Corpus)
try
{
auto name = export_dir->GetName();
HandleLongOrUnprintableString(
L"Name", L"export module name", 2, WarningType::kSuspicious, name);
}
catch (std::exception const& /*e*/)
{
WriteNormal(out, L"WARNING! Failed to read export dir name.", 2);
WarnForCurrentFile(WarningType::kSuspicious);
}
WriteNamedHex(out, L"OrdinalBase", export_dir->GetOrdinalBase(), 2);
WriteNamedHex(
out, L"NumberOfFunctions", export_dir->GetNumberOfFunctions(), 2);
WriteNamedHex(out, L"NumberOfNames", export_dir->GetNumberOfNames(), 2);
WriteNamedHex(
out, L"AddressOfFunctions", export_dir->GetAddressOfFunctions(), 2);
WriteNamedHex(out, L"AddressOfNames", export_dir->GetAddressOfNames(), 2);
WriteNamedHex(
out, L"AddressOfNameOrdinals", export_dir->GetAddressOfNameOrdinals(), 2);
std::set<std::string> export_names;
hadesmem::ExportList const exports(process, pe_file);
if (std::begin(exports) != std::end(exports))
{
WriteNewline(out);
WriteNormal(out, L"Exports:", 2);
}
else
{
WriteNewline(out);
WriteNormal(out, L"WARNING! Empty or invalid export list.", 2);
WarnForCurrentFile(WarningType::kSuspicious);
}
std::uint32_t num_exports = 0U;
for (auto const& e : exports)
{
WriteNewline(out);
// Some legitimate DLLs have well over 1000 exports (e.g. ntdll.dll).
if (num_exports++ == 10000)
{
WriteNormal(
out,
L"WARNING! Processed 10000 exports. Stopping early to avoid resource "
L"exhaustion attacks.",
2);
WarnForCurrentFile(WarningType::kSuspicious);
break;
}
if (e.ByName())
{
auto const name = e.GetName();
// Sample: dllweirdexp.dll
HandleLongOrUnprintableString(
L"Name", L"export name", 3, WarningType::kSuspicious, name);
// PE files can have duplicate exported function names (or even have them
// all identical) because the import hint is used to check the name first
// before performing a search.
// Sample: None ("Import name hint" section of "Undocumented PECOFF"
// whitepaper).
if (!export_names.insert(name).second)
{
WriteNormal(out, L"WARNING! Detected duplicate export name.", 3);
WarnForCurrentFile(WarningType::kSuspicious);
}
}
WriteNamedHex(out, L"ProcedureNumber", e.GetProcedureNumber(), 3);
WriteNamedHex(out, L"OrdinalNumber", e.GetOrdinalNumber(), 3);
if (e.IsForwarded())
{
WriteNamedNormal(out, L"Forwarder", e.GetForwarder().c_str(), 3);
WriteNamedNormal(
out, L"ForwarderModule", e.GetForwarderModule().c_str(), 3);
WriteNamedNormal(
out, L"ForwarderFunction", e.GetForwarderFunction().c_str(), 3);
WriteNamedNormal(
out, L"IsForwardedByOrdinal", e.IsForwardedByOrdinal(), 3);
if (e.IsForwardedByOrdinal())
{
try
{
WriteNamedHex(out, L"ForwarderOrdinal", e.GetForwarderOrdinal(), 3);
}
catch (std::exception const& /*e*/)
{
WriteNormal(out, L"WARNING! ForwarderOrdinal invalid.", 3);
WarnForCurrentFile(WarningType::kSuspicious);
}
}
}
else
{
auto const ep_rva = e.GetRva();
WriteNamedHex(out, L"RVA", e.GetRva(), 3);
auto const ep_va = e.GetVa();
WriteNamedHex(out, L"VA", reinterpret_cast<std::uintptr_t>(ep_va), 3);
if (ep_va)
{
DisassembleEp(process, pe_file, ep_rva, ep_va, 4);
}
else
{
WriteNormal(out, L"WARNING! Export VA is invalid.", 3);
WarnForCurrentFile(WarningType::kSuspicious);
}
}
}
}
void DumpRelocations(hadesmem::Process const& process,
hadesmem::PeFile const& pe_file)
{
if (!HasRelocationsDir(process, pe_file))
{
return;
}
std::wostream& out = GetOutputStreamW();
WriteNewline(out);
hadesmem::RelocationBlockList const reloc_blocks(process, pe_file);
if (std::begin(reloc_blocks) != std::end(reloc_blocks))
{
WriteNormal(out, L"Relocation Blocks:", 1);
}
else
{
// Sample: dllmaxvals.dll (Corkami PE Corpus)
// Sample: fakerelocs.exe (Corkami PE Corpus)
WriteNormal(out, L"WARNING! Relocation block list is invalid.", 1);
WarnForCurrentFile(WarningType::kSuspicious);
}
for (auto const& block : reloc_blocks)
{
WriteNewline(out);
auto const va = block.GetVirtualAddress();
WriteNamedHex(out, L"VirtualAddress", va, 2);
auto const size = block.GetSizeOfBlock();
WriteNamedHex(out, L"SizeOfBlock", block.GetSizeOfBlock(), 2);
WriteNewline(out);
if (!size)
{
WriteNormal(out, L"WARNING! Detected zero sized relocation block.", 2);
WarnForCurrentFile(WarningType::kUnsupported);
continue;
}
WriteNormal(out, L"Relocations:", 2);
hadesmem::RelocationList const relocs(process,
pe_file,
block.GetRelocationDataStart(),
block.GetNumberOfRelocations());
for (auto const& reloc : relocs)
{
WriteNewline(out);
auto const type = reloc.GetType();
WriteNamedHex(out, L"Type", type, 3);
WriteNamedHex(out, L"Offset", reloc.GetOffset(), 3);
// 11 = IMAGE_REL_BASED_HIGH3ADJ
if (type > 11)
{
WriteNormal(out, L"WARNING! Unknown relocation type.", 3);
WarnForCurrentFile(WarningType::kUnsupported);
}
}
}
}
