Merge branch 'patchzyy:main' into main

runtime/include/console_identity.h

@@ -1,38 +1,28 @@
 #pragma once
 
-#include "runtime_config.h"
+#include "nand_path.h"
+#include "nand_settings.h"
 
-#include <algorithm>
 #include <array>
-#include <cctype>
 #include <cstddef>
 #include <cstdint>
-#include <filesystem>
-#include <fstream>
 #include <iomanip>
-#include <optional>
-#include <random>
 #include <sstream>
 #include <string>
-#include <string_view>
 #include <utility>
 
 namespace RuntimeConsoleIdentity {
 
 struct Identity {
     std::string serial;
+    std::string productCode;
+    std::string area;
+    std::string gameRegion;
     std::array<uint8_t, 6> mac;
 };
 
-inline bool IsValidSerial(const std::string& serial) {
-    return serial.size() == 9 &&
-           serial != "000000000" &&
-           std::all_of(serial.begin(), serial.end(),
-                       [](unsigned char value) { return std::isdigit(value) != 0; });
-}
-
 inline Identity FromSerial(std::string serial) {
-    // Keep Nintendo's Wii OUI. The suffix is derived from the persisted serial
+    // Keep Nintendo's Wii OUI. The suffix is derived from the NAND serial
     // so every API exposes one coherent, stable virtual-console identity.
     uint32_t hash = 2166136261u;
     for (const unsigned char value : serial) {
@@ -46,6 +36,7 @@ inline Identity FromSerial(std::string serial) {
 
     return {
         std::move(serial),
+        {}, {}, {},
         {
             0x00,
             0x09,
@@ -57,83 +48,23 @@ inline Identity FromSerial(std::string serial) {
     };
 }
 
-inline std::optional<std::string> ReadSerial(const std::filesystem::path& path) {
-    std::ifstream input(path);
-    std::string line;
-    if (!input || !std::getline(input, line)) {
-        return std::nullopt;
+inline Identity LoadFromNand() {
+    const auto root = RuntimeNandPath::DiscoverNandRootPath();
+    const auto settings = RuntimeNandSettings::Read(root);
+    if (!settings || !RuntimeNandSettings::HasIdentity(*settings)) {
+        RuntimeNandPath::FailNandRoot(
+            "NAND setting.txt is missing or has invalid console identity fields (SERNO, CODE, AREA, GAME)",
+            root / "title/00000001/00000002/data/setting.txt");
     }
-    constexpr std::string_view prefix = "serial=";
-    if (line.rfind(prefix, 0) != 0) {
-        return std::nullopt;
-    }
-    std::string serial = line.substr(prefix.size());
-    if (!IsValidSerial(serial)) {
-        return std::nullopt;
-    }
-    return serial;
-}
-
-inline bool WriteSerial(const std::filesystem::path& path, const std::string& serial) {
-    std::error_code ec;
-    std::filesystem::create_directories(path.parent_path(), ec);
-    if (ec) {
-        return false;
-    }
-
-    std::filesystem::path temporary = path;
-    temporary += ".tmp";
-    {
-        std::ofstream output(temporary, std::ios::trunc);
-        if (!output) {
-            return false;
-        }
-        output << "serial=" << serial << '\n';
-        output.close();
-        if (!output) {
-            return false;
-        }
-    }
-
-    std::filesystem::rename(temporary, path, ec);
-    if (!ec) {
-        return true;
-    }
-    std::filesystem::remove(temporary, ec);
-    return false;
-}
-
-inline std::string GenerateSerial() {
-    std::random_device entropy;
-    std::seed_seq seed{
-        entropy(),
-        entropy(),
-        entropy(),
-        entropy(),
-    };
-    std::mt19937 generator(seed);
-    std::uniform_int_distribution<uint32_t> distribution(100000000u, 999999999u);
-    return std::to_string(distribution(generator));
-}
-
-inline Identity LoadOrCreate(const std::filesystem::path& path) {
-    if (const auto serial = ReadSerial(path)) {
-        return FromSerial(*serial);
-    }
-
-    const std::string generated = GenerateSerial();
-    if (WriteSerial(path, generated)) {
-        return FromSerial(generated);
-    }
-
-    // Remain operational in a read-only environment. This fallback matches
-    // Dolphin's deterministic serial while keeping the same valid identity shape.
-    return FromSerial("123456789");
+    Identity identity = FromSerial(settings->at("SERNO"));
+    identity.productCode = settings->at("CODE");
+    identity.area = settings->at("AREA");
+    identity.gameRegion = settings->at("GAME");
+    return identity;
 }
 
 inline const Identity& Current() {
-    static const Identity identity =
-        LoadOrCreate(RuntimeConfigFile::ApplicationDataDirectory() / "ConsoleIdentity.txt");
+    static const Identity identity = LoadFromNand();
     return identity;
 }
 

runtime/include/nand_path.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include "runtime_config.h"
+#include "nand_settings.h"
 #include "runtime_log.h"
 #include "system_bridge.h"
 
@@ -163,7 +164,7 @@ inline std::filesystem::path CreateManagedNandRoot() {
     return root;
 }
 
-inline std::filesystem::path DiscoverNandRootPath() {
+inline std::filesystem::path ResolveNandRootPath() {
     const std::string configPath = RuntimeConfigFile::NandRoot();
     if (!configPath.empty()) {
         const auto path = ResolveConfiguredPath(configPath);
@@ -179,4 +180,16 @@ inline std::filesystem::path DiscoverNandRootPath() {
     return CreateManagedNandRoot();
 }
 
+inline std::filesystem::path DiscoverNandRootPath() {
+    static const auto root = [] {
+        const auto resolved = ResolveNandRootPath();
+        std::string error;
+        if (!RuntimeNandSettings::Ensure(resolved, error)) {
+            FailNandRoot(error.c_str(), RuntimeNandSettings::FilePath(resolved));
+        }
+        return resolved;
+    }();
+    return root;
+}
+
 } // namespace RuntimeNandPath

runtime/include/nand_save_probe.h

@@ -0,0 +1,59 @@
+#pragma once
+
+#include <filesystem>
+#include <fstream>
+#include <istream>
+
+namespace RuntimeNandSave {
+
+enum class Contents { Missing, Blank, Nonzero, Error };
+enum class ReadAction { Proceed, Missing, Error, RecoveryNeeded };
+
+// A failed read is not evidence that a save is blank. Check badbit before EOF:
+// an I/O failure may set both, whereas a successful short final read sets EOF.
+inline Contents InspectStream(std::istream& input) {
+    if (!input) return Contents::Error;
+    char block[4096];
+    for (;;) {
+        input.read(block, sizeof(block));
+        if (input.bad() || (input.fail() && !input.eof())) return Contents::Error;
+        for (std::streamsize i = 0; i < input.gcount(); ++i) {
+            if (block[i] != 0) return Contents::Nonzero;
+        }
+        if (input.eof()) return Contents::Blank;
+    }
+}
+
+inline Contents InspectFile(const std::filesystem::path& path) {
+    std::error_code ec;
+    const auto status = std::filesystem::symlink_status(path, ec);
+    if (ec && ec != std::errc::no_such_file_or_directory) return Contents::Error;
+    if (!std::filesystem::exists(status)) return Contents::Missing;
+    if (!std::filesystem::is_regular_file(path, ec) || ec) return Contents::Error;
+    std::ifstream input(path, std::ios::binary);
+    return InspectStream(input);
+}
+
+// Probe only read-only opens of the actual save and its exact write shadow.
+// No probe writes, removes, or repairs data, and backups are not save aliases.
+inline ReadAction CheckRead(const std::filesystem::path& path, int mode) {
+    const auto name = path.filename();
+    const bool isMain = name == "rksys.dat";
+    if (mode != 1 || (!isMain && name != "rksys.dat.nandsafe.tmp")) return ReadAction::Proceed;
+    const auto contents = InspectFile(path);
+    if (contents == Contents::Error) return ReadAction::Error;
+    if (contents == Contents::Nonzero) return ReadAction::Proceed;
+    if (isMain) {
+        auto shadow = path;
+        shadow += ".nandsafe.tmp";
+        const auto shadowContents = InspectFile(shadow);
+        if (shadowContents == Contents::Error) return ReadAction::Error;
+        // The next write normally discards an old shadow. Preserve a possible
+        // recovery source when there is no usable original, without promoting
+        // an uncommitted (and potentially incomplete) shadow to the real save.
+        if (shadowContents == Contents::Nonzero) return ReadAction::RecoveryNeeded;
+    }
+    return contents == Contents::Blank ? ReadAction::Missing : ReadAction::Proceed;
+}
+
+} // namespace RuntimeNandSave

runtime/include/nand_settings.h

@@ -0,0 +1,220 @@
+#pragma once
+
+#include <array>
+#include <atomic>
+#include <chrono>
+#include <ctime>
+#include <cstdint>
+#include <filesystem>
+#include <fstream>
+#include <map>
+#include <optional>
+#include <string>
+#include <utility>
+
+#ifdef _WIN32
+#include <windows.h>
+#else
+#include <unistd.h>
+#endif
+
+namespace RuntimeNandSettings {
+
+using Settings = std::map<std::string, std::string>;
+
+inline std::filesystem::path FilePath(const std::filesystem::path& root) {
+    return root / "title/00000001/00000002/data/setting.txt";
+}
+
+// Wii setting.txt is a 256-byte buffer encrypted with a rotating XOR key.
+inline std::optional<Settings> Read(const std::filesystem::path& nandRoot) {
+    std::ifstream input(FilePath(nandRoot), std::ios::binary);
+    std::array<uint8_t, 256> bytes{};
+    if (!input.read(reinterpret_cast<char*>(bytes.data()), bytes.size())) {
+        return std::nullopt;
+    }
+    uint32_t key = 0x73B5DBFAu;
+    std::string decoded;
+    for (const uint8_t byte : bytes) {
+        const char value = static_cast<char>(byte ^ static_cast<uint8_t>(key));
+        key = (key << 1) | (key >> 31);
+        if (value == '\0') {
+            break;
+        }
+        if (value != '\r') {
+            decoded += value;
+        }
+    }
+    Settings settings;
+    for (size_t start = 0; start < decoded.size();) {
+        const size_t end = decoded.find('\n', start);
+        const std::string line = decoded.substr(start, end - start);
+        const size_t equals = line.find('=');
+        if (equals != std::string::npos && equals != 0) {
+            settings.emplace(line.substr(0, equals), line.substr(equals + 1));
+        }
+        if (end == std::string::npos) {
+            break;
+        }
+        start = end + 1;
+    }
+    return settings;
+}
+
+inline bool HasIdentity(const Settings& settings) {
+    const auto serial = settings.find("SERNO");
+    if (serial == settings.end() || serial->second.empty() || serial->second.size() > 9 ||
+        serial->second.find_first_not_of("0123456789") != std::string::npos ||
+        serial->second.find_first_not_of('0') == std::string::npos) {
+        return false;
+    }
+    for (const auto& field : {std::pair{"CODE", 5u}, {"AREA", 3u}, {"GAME", 2u}}) {
+        const auto value = settings.find(field.first);
+        if (value == settings.end() || value->second.empty() ||
+            value->second.size() > field.second) {
+            return false;
+        }
+    }
+    return true;
+}
+
+// Dolphin's normal (non-deterministic) first-boot algorithm. It is independent
+// of the ES device ID. Matching another NAND requires that NAND's saved serial.
+inline std::string GenerateSerial(std::time_t now) {
+    if (now < 0) {
+        return {};
+    }
+    const auto digits = std::to_string(now % 1000000000);
+    return std::string(9 - digits.size(), '0') + digits;
+}
+
+// This recompilation targets the European disc. These are Dolphin's PAL boot
+// defaults; an existing setting.txt always takes precedence, in every region.
+inline std::optional<std::array<uint8_t, 256>> EncodeNew(const std::string& serial) {
+    const Settings identity{{"SERNO", serial}, {"CODE", "LEH"}, {"AREA", "EUR"}, {"GAME", "EU"}};
+    if (!HasIdentity(identity)) {
+        return std::nullopt;
+    }
+    std::array<uint8_t, 256> bytes{};
+    size_t position = 0;
+    uint32_t key = 0x73B5DBFAu;
+    const auto writeByte = [&](char value) {
+        bytes[position++] = static_cast<uint8_t>(value) ^ static_cast<uint8_t>(key);
+        key = (key << 1) | (key >> 31);
+    };
+    for (const std::string& line : {std::string("AREA=EUR\r\n"), std::string("MODEL=RVL-001(EUR)\r\n"),
+             std::string("DVD=0\r\n"), std::string("MPCH=0x7FFE\r\n"), std::string("CODE=LEH\r\n"),
+             "SERNO=" + serial + "\r\n", std::string("VIDEO=PAL\r\n"), std::string("GAME=EU\r\n")}) {
+        for (;;) {
+            if (position + line.size() > bytes.size()) {
+                return std::nullopt;
+            }
+            const auto start = position;
+            const auto savedKey = key;
+            bool hasNull = false;
+            for (const char value : line) {
+                writeByte(value);
+                hasNull |= bytes[position - 1] == 0;
+            }
+            if (!hasNull) {
+                break;
+            }
+            // Nintendo stops at an encoded NUL. Dolphin inserts an extra LF
+            // before this line and retries with the shifted encryption key.
+            position = start;
+            key = savedKey;
+            writeByte('\n');
+        }
+    }
+    return bytes; // The unused tail stays raw zero, as in Dolphin.
+}
+
+// Atomically claim our own scratch directory. A collision belongs to another
+// launch (or a previous crashed launch); leave it untouched and try another name.
+inline std::optional<std::filesystem::path> CreateScratchDirectory(
+    const std::filesystem::path& parent, const std::string& token, std::error_code& ec) {
+    for (unsigned attempt = 0; attempt < 128; ++attempt) {
+        const auto candidate = parent / (".setting-init-" + token + "-" + std::to_string(attempt));
+        ec.clear();
+        if (std::filesystem::create_directory(candidate, ec)) return candidate;
+        if (ec && ec != std::errc::file_exists) return std::nullopt;
+    }
+    ec = std::make_error_code(std::errc::file_exists);
+    return std::nullopt;
+}
+
+// Never replace an existing file, including an unreadable or damaged one.
+// Publish a complete file atomically so simultaneous launches use one identity.
+inline bool Ensure(const std::filesystem::path& root, std::string& error,
+                   std::time_t now = std::time(nullptr)) {
+    const auto path = FilePath(root);
+    std::error_code ec;
+    const auto status = std::filesystem::symlink_status(path, ec);
+    if (ec && ec != std::errc::no_such_file_or_directory) {
+        error = "Cannot inspect NAND setting.txt: " + ec.message();
+        return false;
+    }
+    if (std::filesystem::exists(status)) {
+        const auto existing = Read(root);
+        if (existing && HasIdentity(*existing)) {
+            return true;
+        }
+        error = "Existing NAND setting.txt is unreadable or invalid; restore it from this console's backup";
+        return false;
+    }
+
+    const auto bytes = EncodeNew(GenerateSerial(now));
+    if (!bytes) {
+        error = "Cannot initialize NAND settings: invalid system clock";
+        return false;
+    }
+    ec.clear();
+    std::filesystem::create_directories(path.parent_path(), ec);
+    if (ec) {
+        error = "Cannot create NAND settings directory: " + ec.message();
+        return false;
+    }
+    static std::atomic<unsigned> sequence{0};
+#ifdef _WIN32
+    const auto processId = GetCurrentProcessId();
+#else
+    const auto processId = getpid();
+#endif
+    const auto scratch = CreateScratchDirectory(path.parent_path(),
+        std::to_string(processId) + "-" + std::to_string(
+            std::chrono::steady_clock::now().time_since_epoch().count()) + "-" +
+            std::to_string(sequence++), ec);
+    if (!scratch) {
+        error = "Cannot create temporary NAND settings directory: " + ec.message();
+        return false;
+    }
+    const auto temporary = *scratch / "setting.txt";
+    bool written = false;
+    {
+        std::ofstream output(temporary, std::ios::binary);
+        output.write(reinterpret_cast<const char*>(bytes->data()), bytes->size());
+        output.close();
+        written = static_cast<bool>(output);
+    }
+    bool published = false;
+    if (written) {
+#ifdef _WIN32
+        published = MoveFileExW(temporary.c_str(), path.c_str(), MOVEFILE_WRITE_THROUGH) != 0;
+#else
+        published = ::link(temporary.c_str(), path.c_str()) == 0;
+#endif
+    }
+    std::filesystem::remove(temporary, ec);
+    std::filesystem::remove(*scratch, ec);
+    // A competing launcher may have published its settings first. Always read
+    // the winner from NAND rather than using our unpersisted candidate serial.
+    const auto persisted = Read(root);
+    if (persisted && HasIdentity(*persisted)) {
+        return true;
+    }
+    error = published ? "Cannot read newly initialized NAND setting.txt" :
+                        "Cannot persist NAND setting.txt; check NAND directory permissions";
+    return false;
+}
+
+} // namespace RuntimeNandSettings

runtime/include/sc_serial_contract.h

@@ -0,0 +1,26 @@
+#pragma once
+
+#include <charconv>
+#include <cstddef>
+#include <cstdint>
+#include <string_view>
+#include <system_error>
+
+namespace RuntimeScSerial {
+
+// SCGetProductSN's output is a u32, not a character buffer. DWC loads
+// that word and formats it with the product code to construct csnum.
+template <typename RangeValidator, typename WordWriter>
+uint32_t Write(std::string_view serial, uint32_t address,
+               RangeValidator&& contains, WordWriter&& write32) {
+    if (serial.empty() || serial.size() > 9 ||
+        serial.find_first_not_of("0123456789") != std::string_view::npos) return 0;
+    uint32_t number = 0;
+    const auto parsed = std::from_chars(serial.data(), serial.data() + serial.size(), number);
+    if (parsed.ec != std::errc{} || parsed.ptr != serial.data() + serial.size() ||
+        !address || !contains(address, sizeof(uint32_t))) return 0;
+    write32(address, number);
+    return 1;
+}
+
+} // namespace RuntimeScSerial