avoid saving files on disk

This commit is contained in:
2026-03-13 03:33:18 +03:00
parent 2002bcca83
commit ed9da79d08
6 changed files with 324 additions and 528 deletions

View File

@@ -6,8 +6,8 @@
#include <omath/utility/macho_pattern_scan.hpp>
#include <cstdint>
#include <cstring>
#include <fstream>
#include <vector>
#include "mem_fd_helper.hpp"
using namespace omath;
@@ -16,11 +16,12 @@ namespace
// Mach-O magic numbers
constexpr std::uint32_t mh_magic_64 = 0xFEEDFACF;
constexpr std::uint32_t mh_magic_32 = 0xFEEDFACE;
constexpr std::uint32_t lc_segment = 0x1;
constexpr std::uint32_t lc_segment = 0x1;
constexpr std::uint32_t lc_segment_64 = 0x19;
constexpr std::string_view segment_name = "__TEXT";
constexpr std::string_view section_name = "__text";
#pragma pack(push, 1)
struct MachHeader64
{
@@ -107,249 +108,174 @@ namespace
};
#pragma pack(pop)
// Helper function to create a minimal 64-bit Mach-O file with a __text section
bool write_minimal_macho64_file(const std::string& path, const std::vector<std::uint8_t>& section_bytes)
// Build a minimal 64-bit Mach-O binary in-memory with a __text section
std::vector<std::uint8_t> build_minimal_macho64(const std::vector<std::uint8_t>& section_bytes)
{
std::ofstream f(path, std::ios::binary);
if (!f.is_open())
return false;
constexpr std::size_t load_cmd_size = sizeof(SegmentCommand64) + sizeof(Section64);
const std::size_t section_offset = sizeof(MachHeader64) + load_cmd_size;
// Calculate sizes
constexpr std::size_t header_size = sizeof(MachHeader64);
constexpr std::size_t segment_size = sizeof(SegmentCommand64);
constexpr std::size_t section_size = sizeof(Section64);
constexpr std::size_t load_cmd_size = segment_size + section_size;
// Section data will start after headers
const std::size_t section_offset = header_size + load_cmd_size;
std::vector<std::uint8_t> buf(section_offset + section_bytes.size(), 0u);
// Create Mach-O header
MachHeader64 header{};
header.magic = mh_magic_64;
header.cputype = 0x01000007; // CPU_TYPE_X86_64
header.cpusubtype = 0x3; // CPU_SUBTYPE_X86_64_ALL
header.filetype = 0x2; // MH_EXECUTE
header.ncmds = 1;
header.sizeofcmds = static_cast<std::uint32_t>(load_cmd_size);
header.flags = 0;
header.reserved = 0;
auto* header = reinterpret_cast<MachHeader64*>(buf.data());
header->magic = mh_magic_64;
header->cputype = 0x01000007; // CPU_TYPE_X86_64
header->cpusubtype = 0x3;
header->filetype = 0x2; // MH_EXECUTE
header->ncmds = 1;
header->sizeofcmds = static_cast<std::uint32_t>(load_cmd_size);
f.write(reinterpret_cast<const char*>(&header), sizeof(header));
auto* segment = reinterpret_cast<SegmentCommand64*>(buf.data() + sizeof(MachHeader64));
segment->cmd = lc_segment_64;
segment->cmdsize = static_cast<std::uint32_t>(load_cmd_size);
std::ranges::copy(segment_name, segment->segname);
segment->vmaddr = 0x100000000;
segment->vmsize = section_bytes.size();
segment->fileoff = section_offset;
segment->filesize = section_bytes.size();
segment->maxprot = 7;
segment->initprot = 5;
segment->nsects = 1;
// Create segment command
SegmentCommand64 segment{};
segment.cmd = lc_segment_64;
segment.cmdsize = static_cast<std::uint32_t>(load_cmd_size);
std::ranges::copy(segment_name, segment.segname);
segment.vmaddr = 0x100000000;
segment.vmsize = section_bytes.size();
segment.fileoff = section_offset;
segment.filesize = section_bytes.size();
segment.maxprot = 7; // VM_PROT_ALL
segment.initprot = 5; // VM_PROT_READ | VM_PROT_EXECUTE
segment.nsects = 1;
segment.flags = 0;
auto* section = reinterpret_cast<Section64*>(buf.data() + sizeof(MachHeader64) + sizeof(SegmentCommand64));
std::ranges::copy(section_name, section->sectname);
std::ranges::copy(segment_name, section->segname);
section->addr = 0x100000000;
section->size = section_bytes.size();
section->offset = static_cast<std::uint32_t>(section_offset);
f.write(reinterpret_cast<const char*>(&segment), sizeof(segment));
// Create section
Section64 section{};
std::ranges::copy(section_name, section.sectname);
std::ranges::copy(segment_name, segment.segname);
section.addr = 0x100000000;
section.size = section_bytes.size();
section.offset = static_cast<std::uint32_t>(section_offset);
section.align = 0;
section.reloff = 0;
section.nreloc = 0;
section.flags = 0;
section.reserved1 = 0;
section.reserved2 = 0;
section.reserved3 = 0;
f.write(reinterpret_cast<const char*>(&section), sizeof(section));
// Write section data
f.write(reinterpret_cast<const char*>(section_bytes.data()), static_cast<std::streamsize>(section_bytes.size()));
f.close();
return true;
std::memcpy(buf.data() + section_offset, section_bytes.data(), section_bytes.size());
return buf;
}
// Helper function to create a minimal 32-bit Mach-O file with a __text section
bool write_minimal_macho32_file(const std::string& path, const std::vector<std::uint8_t>& section_bytes)
// Build a minimal 32-bit Mach-O binary in-memory with a __text section
std::vector<std::uint8_t> build_minimal_macho32(const std::vector<std::uint8_t>& section_bytes)
{
std::ofstream f(path, std::ios::binary);
if (!f.is_open())
return false;
constexpr std::size_t load_cmd_size = sizeof(SegmentCommand32) + sizeof(Section32);
constexpr std::size_t section_offset = sizeof(MachHeader32) + load_cmd_size;
// Calculate sizes
constexpr std::size_t header_size = sizeof(MachHeader32);
constexpr std::size_t segment_size = sizeof(SegmentCommand32);
constexpr std::size_t section_size = sizeof(Section32);
constexpr std::size_t load_cmd_size = segment_size + section_size;
std::vector<std::uint8_t> buf(section_offset + section_bytes.size(), 0u);
// Section data will start after headers
constexpr std::size_t section_offset = header_size + load_cmd_size;
auto* header = reinterpret_cast<MachHeader32*>(buf.data());
header->magic = mh_magic_32;
header->cputype = 0x7;
header->cpusubtype = 0x3;
header->filetype = 0x2;
header->ncmds = 1;
header->sizeofcmds = static_cast<std::uint32_t>(load_cmd_size);
// Create Mach-O header
MachHeader32 header{};
header.magic = mh_magic_32;
header.cputype = 0x7; // CPU_TYPE_X86
header.cpusubtype = 0x3; // CPU_SUBTYPE_X86_ALL
header.filetype = 0x2; // MH_EXECUTE
header.ncmds = 1;
header.sizeofcmds = static_cast<std::uint32_t>(load_cmd_size);
header.flags = 0;
auto* segment = reinterpret_cast<SegmentCommand32*>(buf.data() + sizeof(MachHeader32));
segment->cmd = lc_segment;
segment->cmdsize = static_cast<std::uint32_t>(load_cmd_size);
std::ranges::copy(segment_name, segment->segname);
segment->vmaddr = 0x1000;
segment->vmsize = static_cast<std::uint32_t>(section_bytes.size());
segment->fileoff = static_cast<std::uint32_t>(section_offset);
segment->filesize = static_cast<std::uint32_t>(section_bytes.size());
segment->maxprot = 7;
segment->initprot = 5;
segment->nsects = 1;
f.write(reinterpret_cast<const char*>(&header), sizeof(header));
auto* section = reinterpret_cast<Section32*>(buf.data() + sizeof(MachHeader32) + sizeof(SegmentCommand32));
std::ranges::copy(section_name, section->sectname);
std::ranges::copy(segment_name, section->segname);
section->addr = 0x1000;
section->size = static_cast<std::uint32_t>(section_bytes.size());
section->offset = static_cast<std::uint32_t>(section_offset);
// Create segment command
SegmentCommand32 segment{};
segment.cmd = lc_segment;
segment.cmdsize = static_cast<std::uint32_t>(load_cmd_size);
std::ranges::copy(segment_name, segment.segname);
segment.vmaddr = 0x1000;
segment.vmsize = static_cast<std::uint32_t>(section_bytes.size());
segment.fileoff = static_cast<std::uint32_t>(section_offset);
segment.filesize = static_cast<std::uint32_t>(section_bytes.size());
segment.maxprot = 7; // VM_PROT_ALL
segment.initprot = 5; // VM_PROT_READ | VM_PROT_EXECUTE
segment.nsects = 1;
segment.flags = 0;
f.write(reinterpret_cast<const char*>(&segment), sizeof(segment));
// Create section
Section32 section{};
std::ranges::copy(section_name, section.sectname);
std::ranges::copy(segment_name, segment.segname);
section.addr = 0x1000;
section.size = static_cast<std::uint32_t>(section_bytes.size());
section.offset = static_cast<std::uint32_t>(section_offset);
section.align = 0;
section.reloff = 0;
section.nreloc = 0;
section.flags = 0;
section.reserved1 = 0;
section.reserved2 = 0;
f.write(reinterpret_cast<const char*>(&section), sizeof(section));
// Write section data
f.write(reinterpret_cast<const char*>(section_bytes.data()), static_cast<std::streamsize>(section_bytes.size()));
f.close();
return true;
std::memcpy(buf.data() + section_offset, section_bytes.data(), section_bytes.size());
return buf;
}
} // namespace
// Test scanning for a pattern that exists in a 64-bit Mach-O file
TEST(unit_test_macho_pattern_scan_file, ScanFindsPattern64)
{
constexpr std::string_view path = "./test_minimal_macho64.bin";
const std::vector<std::uint8_t> bytes = {0x55, 0x48, 0x89, 0xE5, 0x90, 0x90}; // push rbp; mov rbp, rsp; nop; nop
ASSERT_TRUE(write_minimal_macho64_file(path.data(), bytes));
const std::vector<std::uint8_t> bytes = {0x55, 0x48, 0x89, 0xE5, 0x90, 0x90};
const auto f = MemFdFile::create(build_minimal_macho64(bytes));
ASSERT_TRUE(f.valid());
const auto res = MachOPatternScanner::scan_for_pattern_in_file(path, "55 48 89 E5", "__text");
const auto res = MachOPatternScanner::scan_for_pattern_in_file(f.path(), "55 48 89 E5", "__text");
EXPECT_TRUE(res.has_value());
if (res.has_value())
{
EXPECT_EQ(res->target_offset, 0);
}
}
// Test scanning for a pattern that exists in a 32-bit Mach-O file
TEST(unit_test_macho_pattern_scan_file, ScanFindsPattern32)
{
constexpr std::string_view path = "./test_minimal_macho32.bin";
const std::vector<std::uint8_t> bytes = {0x55, 0x89, 0xE5, 0x90, 0x90}; // push ebp; mov ebp, esp; nop; nop
ASSERT_TRUE(write_minimal_macho32_file(path.data(), bytes));
const std::vector<std::uint8_t> bytes = {0x55, 0x89, 0xE5, 0x90, 0x90};
const auto f = MemFdFile::create(build_minimal_macho32(bytes));
ASSERT_TRUE(f.valid());
const auto res = MachOPatternScanner::scan_for_pattern_in_file(path, "55 89 E5", "__text");
const auto res = MachOPatternScanner::scan_for_pattern_in_file(f.path(), "55 89 E5", "__text");
EXPECT_TRUE(res.has_value());
if (res.has_value())
{
EXPECT_EQ(res->target_offset, 0);
}
}
// Test scanning for a pattern that does not exist
TEST(unit_test_macho_pattern_scan_file, ScanMissingPattern)
{
constexpr std::string_view path = "./test_minimal_macho_missing.bin";
const std::vector<std::uint8_t> bytes = {0x00, 0x01, 0x02, 0x03};
ASSERT_TRUE(write_minimal_macho64_file(path.data(), bytes));
const auto f = MemFdFile::create(build_minimal_macho64(bytes));
ASSERT_TRUE(f.valid());
const auto res = MachOPatternScanner::scan_for_pattern_in_file(path, "FF EE DD", "__text");
const auto res = MachOPatternScanner::scan_for_pattern_in_file(f.path(), "FF EE DD", "__text");
EXPECT_FALSE(res.has_value());
}
// Test scanning for a pattern at a non-zero offset
TEST(unit_test_macho_pattern_scan_file, ScanPatternAtOffset)
{
constexpr std::string_view path = "./test_minimal_macho_offset.bin";
const std::vector<std::uint8_t> bytes = {0x90, 0x90, 0x90, 0x55, 0x48, 0x89, 0xE5}; // nops then pattern
ASSERT_TRUE(write_minimal_macho64_file(path.data(), bytes));
const std::vector<std::uint8_t> bytes = {0x90, 0x90, 0x90, 0x55, 0x48, 0x89, 0xE5};
const auto f = MemFdFile::create(build_minimal_macho64(bytes));
ASSERT_TRUE(f.valid());
const auto res = MachOPatternScanner::scan_for_pattern_in_file(path, "55 48 89 E5", "__text");
const auto res = MachOPatternScanner::scan_for_pattern_in_file(f.path(), "55 48 89 E5", "__text");
EXPECT_TRUE(res.has_value());
if (res.has_value())
{
EXPECT_EQ(res->target_offset, 3);
}
}
// Test scanning with wildcards
TEST(unit_test_macho_pattern_scan_file, ScanWithWildcard)
{
constexpr std::string_view path = "./test_minimal_macho_wildcard.bin";
const std::vector<std::uint8_t> bytes = {0x55, 0x48, 0x89, 0xE5, 0x90};
ASSERT_TRUE(write_minimal_macho64_file(path.data(), bytes));
const auto f = MemFdFile::create(build_minimal_macho64(bytes));
ASSERT_TRUE(f.valid());
const auto res = MachOPatternScanner::scan_for_pattern_in_file(path, "55 ? 89 E5", "__text");
const auto res = MachOPatternScanner::scan_for_pattern_in_file(f.path(), "55 ? 89 E5", "__text");
EXPECT_TRUE(res.has_value());
}
// Test scanning a non-existent file
TEST(unit_test_macho_pattern_scan_file, ScanNonExistentFile)
{
const auto res = MachOPatternScanner::scan_for_pattern_in_file("/non/existent/file.bin", "55 48", "__text");
EXPECT_FALSE(res.has_value());
}
// Test scanning an invalid (non-Mach-O) file
TEST(unit_test_macho_pattern_scan_file, ScanInvalidFile)
{
constexpr std::string_view path = "./test_invalid_macho.bin";
std::ofstream f(path.data(), std::ios::binary);
const std::vector<std::uint8_t> garbage = {0x00, 0x01, 0x02, 0x03, 0x04, 0x05};
f.write(reinterpret_cast<const char*>(garbage.data()), static_cast<std::streamsize>(garbage.size()));
f.close();
const auto f = MemFdFile::create(garbage);
ASSERT_TRUE(f.valid());
const auto res = MachOPatternScanner::scan_for_pattern_in_file(path, "55 48", "__text");
const auto res = MachOPatternScanner::scan_for_pattern_in_file(f.path(), "55 48", "__text");
EXPECT_FALSE(res.has_value());
}
// Test scanning for a non-existent section
TEST(unit_test_macho_pattern_scan_file, ScanNonExistentSection)
{
constexpr std::string_view path = "./test_minimal_macho_nosect.bin";
const std::vector<std::uint8_t> bytes = {0x55, 0x48, 0x89, 0xE5};
ASSERT_TRUE(write_minimal_macho64_file(path.data(), bytes));
const auto f = MemFdFile::create(build_minimal_macho64(bytes));
ASSERT_TRUE(f.valid());
const auto res = MachOPatternScanner::scan_for_pattern_in_file(path, "55 48", "__nonexistent");
const auto res = MachOPatternScanner::scan_for_pattern_in_file(f.path(), "55 48", "__nonexistent");
EXPECT_FALSE(res.has_value());
}
// Test scanning with null module base address
TEST(unit_test_macho_pattern_scan_loaded, ScanNullModule)
{
const auto res = MachOPatternScanner::scan_for_pattern_in_loaded_module(nullptr, "55 48", "__text");
EXPECT_FALSE(res.has_value());
}
// Test scanning in loaded module with invalid magic
TEST(unit_test_macho_pattern_scan_loaded, ScanInvalidMagic)
{
std::vector<std::uint8_t> invalid_data(256, 0x00);