yuzu/src/core/loader/nso.cpp

300 lines
10 KiB
C++

// Copyright 2017 Citra Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <vector>
#include <lz4.h>
#include "common/logging/log.h"
#include "common/swap.h"
#include "core/hle/kernel/process.h"
#include "core/hle/kernel/resource_limit.h"
#include "core/loader/nso.h"
#include "core/memory.h"
namespace Loader {
enum class RelocationType : u32 { ABS64 = 257, GLOB_DAT = 1025, JUMP_SLOT = 1026, RELATIVE = 1027 };
enum DynamicType : u32 {
DT_NULL = 0,
DT_PLTRELSZ = 2,
DT_STRTAB = 5,
DT_SYMTAB = 6,
DT_RELA = 7,
DT_RELASZ = 8,
DT_STRSZ = 10,
DT_JMPREL = 23,
};
struct NsoSegmentHeader {
u32_le offset;
u32_le location;
u32_le size;
u32_le alignment;
};
static_assert(sizeof(NsoSegmentHeader) == 0x10, "NsoSegmentHeader has incorrect size.");
struct NsoHeader {
u32_le magic;
INSERT_PADDING_BYTES(0xc);
std::array<NsoSegmentHeader, 3> segments; // Text, RoData, Data (in that order)
u32_le bss_size;
INSERT_PADDING_BYTES(0x1c);
std::array<u32_le, 3> segments_compressed_size;
};
static_assert(sizeof(NsoHeader) == 0x6c, "NsoHeader has incorrect size.");
struct ModHeader {
INSERT_PADDING_BYTES(0x4);
u32_le offset_to_start; // Always 8
u32_le magic;
u32_le dynamic_offset;
u32_le bss_start_offset;
u32_le bss_end_offset;
u32_le eh_frame_hdr_start_offset;
u32_le eh_frame_hdr_end_offset;
u32_le module_offset; // Offset to runtime-generated module object. typically equal to .bss base
};
static_assert(sizeof(ModHeader) == 0x24, "ModHeader has incorrect size.");
FileType AppLoader_NSO::IdentifyType(FileUtil::IOFile& file) {
u32 magic = 0;
file.Seek(0, SEEK_SET);
if (1 != file.ReadArray<u32>(&magic, 1)) {
return FileType::Error;
}
if (MakeMagic('N', 'S', 'O', '0') == magic) {
return FileType::NSO;
}
return FileType::Error;
}
static std::vector<u8> ReadSegment(FileUtil::IOFile& file, const NsoSegmentHeader& header,
int compressed_size) {
std::vector<u8> compressed_data;
compressed_data.resize(compressed_size);
file.Seek(header.offset, SEEK_SET);
if (compressed_size != file.ReadBytes(compressed_data.data(), compressed_size)) {
LOG_CRITICAL(Loader, "Failed to read %d NSO LZ4 compressed bytes", compressed_size);
return {};
}
std::vector<u8> uncompressed_data;
uncompressed_data.resize(header.size);
const int bytes_uncompressed =
LZ4_decompress_safe_partial(reinterpret_cast<const char*>(compressed_data.data()),
reinterpret_cast<char*>(uncompressed_data.data()),
compressed_size, header.size, header.size);
ASSERT_MSG(bytes_uncompressed == header.size, "%d != %d", bytes_uncompressed, header.size);
return uncompressed_data;
}
void AppLoader_NSO::WriteRelocations(const std::vector<Symbol>& symbols, VAddr load_base,
u64 relocation_offset, u64 size, bool is_jump_relocation) {
for (u64 i = 0; i < size; i += 0x18) {
VAddr addr = load_base + relocation_offset + i;
u64 offset = Memory::Read64(addr);
u64 info = Memory::Read64(addr + 8);
u64 addend_unsigned = Memory::Read64(addr + 16);
s64 addend{};
std::memcpy(&addend, &addend_unsigned, sizeof(u64));
RelocationType rtype = static_cast<RelocationType>(info & 0xFFFFFFFF);
u32 rsym = static_cast<u32>(info >> 32);
VAddr ea = load_base + offset;
const Symbol& symbol = symbols[rsym];
switch (rtype) {
case RelocationType::RELATIVE:
if (!symbol.name.empty()) {
exports[symbol.name] = load_base + addend;
}
Memory::Write64(ea, load_base + addend);
break;
case RelocationType::JUMP_SLOT:
case RelocationType::GLOB_DAT:
if (!symbol.value) {
imports[symbol.name] = {ea, 0};
} else {
exports[symbol.name] = symbol.value;
Memory::Write64(ea, symbol.value);
}
break;
case RelocationType::ABS64:
if (!symbol.value) {
imports[symbol.name] = {ea, addend};
} else {
exports[symbol.name] = symbol.value + addend;
Memory::Write64(ea, symbol.value + addend);
}
break;
default:
LOG_CRITICAL(Loader, "Unknown relocation type: %d", rtype);
break;
}
}
}
void AppLoader_NSO::Relocate(VAddr load_base, VAddr dynamic_section_addr) {
std::map<u64, u64> dynamic;
while (1) {
u64 tag = Memory::Read64(dynamic_section_addr);
u64 value = Memory::Read64(dynamic_section_addr + 8);
dynamic_section_addr += 16;
if (tag == DT_NULL) {
break;
}
dynamic[tag] = value;
}
u64 strtabsize = dynamic[DT_STRSZ];
std::vector<u8> strtab;
strtab.resize(strtabsize);
Memory::ReadBlock(load_base + dynamic[DT_STRTAB], strtab.data(), strtabsize);
VAddr addr = load_base + dynamic[DT_SYMTAB];
std::vector<Symbol> symbols;
while (1) {
const u32 stname = Memory::Read32(addr);
const u16 stshndx = Memory::Read16(addr + 6);
const u64 stvalue = Memory::Read64(addr + 8);
addr += 24;
if (stname >= strtabsize) {
break;
}
std::string name = reinterpret_cast<char*>(&strtab[stname]);
if (stvalue) {
exports[name] = load_base + stvalue;
symbols.emplace_back(std::move(name), load_base + stvalue);
} else {
symbols.emplace_back(std::move(name), 0);
}
}
if (dynamic.find(DT_RELA) != dynamic.end()) {
WriteRelocations(symbols, load_base, dynamic[DT_RELA], dynamic[DT_RELASZ], false);
}
if (dynamic.find(DT_JMPREL) != dynamic.end()) {
WriteRelocations(symbols, load_base, dynamic[DT_JMPREL], dynamic[DT_PLTRELSZ], true);
}
}
VAddr AppLoader_NSO::GetEntryPoint(VAddr load_base) const {
// Find nnMain function, set entrypoint to that address
const auto& search = exports.find("nnMain");
if (search != exports.end()) {
return search->second;
}
LOG_ERROR(Loader, "Unable to find entrypoint, defaulting to: 0x%llx", load_base);
return load_base;
}
static constexpr u32 PageAlignSize(u32 size) {
return (size + Memory::PAGE_MASK) & ~Memory::PAGE_MASK;
}
bool AppLoader_NSO::LoadNso(const std::string& path, VAddr load_base) {
FileUtil::IOFile file(path, "rb");
if (!file.IsOpen()) {
return {};
}
// Read NSO header
NsoHeader nso_header{};
file.Seek(0, SEEK_SET);
if (sizeof(NsoHeader) != file.ReadBytes(&nso_header, sizeof(NsoHeader))) {
return {};
}
if (nso_header.magic != MakeMagic('N', 'S', 'O', '0')) {
return {};
}
// Build program image
Kernel::SharedPtr<Kernel::CodeSet> codeset = Kernel::CodeSet::Create("", 0);
std::vector<u8> program_image;
for (int i = 0; i < nso_header.segments.size(); ++i) {
std::vector<u8> data =
ReadSegment(file, nso_header.segments[i], nso_header.segments_compressed_size[i]);
program_image.resize(nso_header.segments[i].location);
program_image.insert(program_image.end(), data.begin(), data.end());
codeset->segments[i].addr = nso_header.segments[i].location;
codeset->segments[i].offset = nso_header.segments[i].location;
codeset->segments[i].size = PageAlignSize(static_cast<u32>(data.size()));
}
// Read MOD header
ModHeader mod_header{};
u32 bss_size{Memory::PAGE_SIZE}; // Default .bss to page size if MOD0 section doesn't exist
std::memcpy(&mod_header, program_image.data(), sizeof(ModHeader));
const bool has_mod_header{mod_header.magic == MakeMagic('M', 'O', 'D', '0')};
if (has_mod_header) {
// Resize program image to include .bss section and page align each section
bss_size = PageAlignSize(mod_header.bss_end_offset - mod_header.bss_start_offset);
codeset->data.size += bss_size;
}
program_image.resize(PageAlignSize(static_cast<u32>(program_image.size()) + bss_size));
// Load codeset for current process
codeset->name = path;
codeset->memory = std::make_shared<std::vector<u8>>(std::move(program_image));
Kernel::g_current_process->LoadModule(codeset, load_base);
// Relocate symbols if there was a proper MOD header - This must happen after the image has been
// loaded into memory
if (has_mod_header) {
Relocate(load_base, load_base + mod_header.offset_to_start + mod_header.dynamic_offset);
}
return true;
}
ResultStatus AppLoader_NSO::Load() {
if (is_loaded) {
return ResultStatus::ErrorAlreadyLoaded;
}
if (!file.IsOpen()) {
return ResultStatus::Error;
}
// Load and relocate "main" and "sdk" NSO
static constexpr VAddr main_base{0x10000000};
Kernel::g_current_process = Kernel::Process::Create("main");
if (!LoadNso(filepath, main_base)) {
return ResultStatus::ErrorInvalidFormat;
}
const std::string sdkpath = filepath.substr(0, filepath.find_last_of("/\\")) + "/sdk";
if (!LoadNso(sdkpath, 0x20000000)) {
LOG_WARNING(Loader, "failed to find SDK NSO");
}
Kernel::g_current_process->svc_access_mask.set();
Kernel::g_current_process->address_mappings = default_address_mappings;
Kernel::g_current_process->resource_limit =
Kernel::ResourceLimit::GetForCategory(Kernel::ResourceLimitCategory::APPLICATION);
Kernel::g_current_process->Run(GetEntryPoint(main_base), 48, Kernel::DEFAULT_STACK_SIZE);
// Resolve imports
for (const auto& import : imports) {
const auto& search = exports.find(import.first);
if (search != exports.end()) {
Memory::Write64(import.second.ea, search->second + import.second.addend);
} else {
LOG_ERROR(Loader, "Unresolved import: %s", import.first.c_str());
}
}
is_loaded = true;
return ResultStatus::Success;
}
} // namespace Loader