6 files changed, 431 insertions, 15 deletions

diff --git a/src/core/hle/service/ldr/ldr.cpp b/src/core/hle/service/ldr/ldr.cpp
index d607d985e..b43f1f054 100644
--- a/src/core/hle/service/ldr/ldr.cpp
+++ b/src/core/hle/service/ldr/ldr.cpp
@@ -4,7 +4,10 @@
 
 #include <memory>
 #include <fmt/format.h>
+#include <mbedtls/sha256.h>
 
+#include "common/alignment.h"
+#include "common/hex_util.h"
 #include "core/hle/ipc_helpers.h"
 #include "core/hle/kernel/process.h"
 #include "core/hle/service/ldr/ldr.h"
@@ -13,6 +16,38 @@
 
 namespace Service::LDR {
 
+namespace ErrCodes {
+enum {
+    InvalidMemoryState = 51,
+    InvalidNRO = 52,
+    InvalidNRR = 53,
+    MissingNRRHash = 54,
+    MaximumNRO = 55,
+    MaximumNRR = 56,
+    AlreadyLoaded = 57,
+    InvalidAlignment = 81,
+    InvalidSize = 82,
+    InvalidNROAddress = 84,
+    InvalidNRRAddress = 85,
+    NotInitialized = 87,
+};
+}
+
+constexpr ResultCode ERROR_INVALID_MEMORY_STATE(ErrorModule::Loader, ErrCodes::InvalidMemoryState);
+constexpr ResultCode ERROR_INVALID_NRO(ErrorModule::Loader, ErrCodes::InvalidNRO);
+constexpr ResultCode ERROR_INVALID_NRR(ErrorModule::Loader, ErrCodes::InvalidNRR);
+constexpr ResultCode ERROR_MISSING_NRR_HASH(ErrorModule::Loader, ErrCodes::MissingNRRHash);
+constexpr ResultCode ERROR_MAXIMUM_NRO(ErrorModule::Loader, ErrCodes::MaximumNRO);
+constexpr ResultCode ERROR_MAXIMUM_NRR(ErrorModule::Loader, ErrCodes::MaximumNRR);
+constexpr ResultCode ERROR_ALREADY_LOADED(ErrorModule::Loader, ErrCodes::AlreadyLoaded);
+constexpr ResultCode ERROR_INVALID_ALIGNMENT(ErrorModule::Loader, ErrCodes::InvalidAlignment);
+constexpr ResultCode ERROR_INVALID_SIZE(ErrorModule::Loader, ErrCodes::InvalidSize);
+constexpr ResultCode ERROR_INVALID_NRO_ADDRESS(ErrorModule::Loader, ErrCodes::InvalidNROAddress);
+constexpr ResultCode ERROR_INVALID_NRR_ADDRESS(ErrorModule::Loader, ErrCodes::InvalidNRRAddress);
+constexpr ResultCode ERROR_NOT_INITIALIZED(ErrorModule::Loader, ErrCodes::NotInitialized);
+
+constexpr u64 MAXIMUM_LOADED_RO = 0x40;
+
 class DebugMonitor final : public ServiceFramework<DebugMonitor> {
 public:
     explicit DebugMonitor() : ServiceFramework{"ldr:dmnt"} {
@@ -64,9 +99,9 @@ public:
         // clang-format off
         static const FunctionInfo functions[] = {
             {0, &RelocatableObject::LoadNro, "LoadNro"},
-            {1, nullptr, "UnloadNro"},
+            {1, &RelocatableObject::UnloadNro, "UnloadNro"},
             {2, &RelocatableObject::LoadNrr, "LoadNrr"},
-            {3, nullptr, "UnloadNrr"},
+            {3, &RelocatableObject::UnloadNrr, "UnloadNrr"},
             {4, &RelocatableObject::Initialize, "Initialize"},
         };
         // clang-format on
@@ -75,9 +110,123 @@ public:
     }
 
     void LoadNrr(Kernel::HLERequestContext& ctx) {
+        IPC::RequestParser rp{ctx};
+        rp.Skip(2, false);
+        const VAddr nrr_addr{rp.Pop<VAddr>()};
+        const u64 nrr_size{rp.Pop<u64>()};
+
+        if (!initialized) {
+            LOG_ERROR(Service_LDR, "LDR:RO not initialized before use!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_NOT_INITIALIZED);
+            return;
+        }
+
+        if (nrr.size() >= MAXIMUM_LOADED_RO) {
+            LOG_ERROR(Service_LDR, "Loading new NRR would exceed the maximum number of loaded NRRs "
+                                   "(0x40)! Failing...");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_MAXIMUM_NRR);
+            return;
+        }
+
+        // NRR Address does not fall on 0x1000 byte boundary
+        if (!Common::Is4KBAligned(nrr_addr)) {
+            LOG_ERROR(Service_LDR, "NRR Address has invalid alignment (actual {:016X})!", nrr_addr);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_ALIGNMENT);
+            return;
+        }
+
+        // NRR Size is zero or causes overflow
+        if (nrr_addr + nrr_size <= nrr_addr || nrr_size == 0 || !Common::Is4KBAligned(nrr_size)) {
+            LOG_ERROR(Service_LDR, "NRR Size is invalid! (nrr_address={:016X}, nrr_size={:016X})",
+                      nrr_addr, nrr_size);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_SIZE);
+            return;
+        }
+        // Read NRR data from memory
+        std::vector<u8> nrr_data(nrr_size);
+        Memory::ReadBlock(nrr_addr, nrr_data.data(), nrr_size);
+        NRRHeader header;
+        std::memcpy(&header, nrr_data.data(), sizeof(NRRHeader));
+
+        if (header.magic != Common::MakeMagic('N', 'R', 'R', '0')) {
+            LOG_ERROR(Service_LDR, "NRR did not have magic 'NRR0' (actual {:08X})!", header.magic);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_NRR);
+            return;
+        }
+
+        if (header.size != nrr_size) {
+            LOG_ERROR(Service_LDR,
+                      "NRR header reported size did not match LoadNrr parameter size! "
+                      "(header_size={:016X}, loadnrr_size={:016X})",
+                      header.size, nrr_size);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_SIZE);
+            return;
+        }
+
+        if (Core::CurrentProcess()->GetTitleID() != header.title_id) {
+            LOG_ERROR(Service_LDR,
+                      "Attempting to load NRR with title ID other than current process. (actual "
+                      "{:016X})!",
+                      header.title_id);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_NRR);
+            return;
+        }
+
+        std::vector<SHA256Hash> hashes;
+
+        // Copy all hashes in the NRR (specified by hash count/hash offset) into vector.
+        for (std::size_t i = header.hash_offset;
+             i < (header.hash_offset + (header.hash_count * sizeof(SHA256Hash))); i += 8) {
+            SHA256Hash hash;
+            std::memcpy(hash.data(), nrr_data.data() + i, sizeof(SHA256Hash));
+            hashes.emplace_back(hash);
+        }
+
+        nrr.insert_or_assign(nrr_addr, std::move(hashes));
+
+        IPC::ResponseBuilder rb{ctx, 2};
+        rb.Push(RESULT_SUCCESS);
+    }
+
+    void UnloadNrr(Kernel::HLERequestContext& ctx) {
+        if (!initialized) {
+            LOG_ERROR(Service_LDR, "LDR:RO not initialized before use!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_NOT_INITIALIZED);
+            return;
+        }
+
+        IPC::RequestParser rp{ctx};
+        rp.Skip(2, false);
+        const auto nrr_addr{rp.Pop<VAddr>()};
+
+        if (!Common::Is4KBAligned(nrr_addr)) {
+            LOG_ERROR(Service_LDR, "NRR Address has invalid alignment (actual {:016X})!", nrr_addr);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_ALIGNMENT);
+            return;
+        }
+
+        const auto iter = nrr.find(nrr_addr);
+        if (iter == nrr.end()) {
+            LOG_ERROR(Service_LDR,
+                      "Attempting to unload NRR which has not been loaded! (addr={:016X})",
+                      nrr_addr);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_NRR_ADDRESS);
+            return;
+        }
+
+        nrr.erase(iter);
         IPC::ResponseBuilder rb{ctx, 2};
         rb.Push(RESULT_SUCCESS);
-        LOG_WARNING(Service_LDR, "(STUBBED) called");
     }
 
     void LoadNro(Kernel::HLERequestContext& ctx) {
@@ -88,33 +237,253 @@ public:
         const VAddr bss_addr{rp.Pop<VAddr>()};
         const u64 bss_size{rp.Pop<u64>()};
 
+        if (!initialized) {
+            LOG_ERROR(Service_LDR, "LDR:RO not initialized before use!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_NOT_INITIALIZED);
+            return;
+        }
+
+        if (nro.size() >= MAXIMUM_LOADED_RO) {
+            LOG_ERROR(Service_LDR, "Loading new NRO would exceed the maximum number of loaded NROs "
+                                   "(0x40)! Failing...");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_MAXIMUM_NRO);
+            return;
+        }
+
+        // NRO Address does not fall on 0x1000 byte boundary
+        if (!Common::Is4KBAligned(nro_addr)) {
+            LOG_ERROR(Service_LDR, "NRO Address has invalid alignment (actual {:016X})!", nro_addr);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_ALIGNMENT);
+            return;
+        }
+
+        // NRO Size or BSS Size is zero or causes overflow
+        const auto nro_size_valid =
+            nro_size != 0 && nro_addr + nro_size > nro_addr && Common::Is4KBAligned(nro_size);
+        const auto bss_size_valid =
+            nro_size + bss_size >= nro_size && (bss_size == 0 || bss_addr + bss_size > bss_addr);
+
+        if (!nro_size_valid || !bss_size_valid) {
+            LOG_ERROR(Service_LDR,
+                      "NRO Size or BSS Size is invalid! (nro_address={:016X}, nro_size={:016X}, "
+                      "bss_address={:016X}, bss_size={:016X})",
+                      nro_addr, nro_size, bss_addr, bss_size);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_SIZE);
+            return;
+        }
+
         // Read NRO data from memory
         std::vector<u8> nro_data(nro_size);
         Memory::ReadBlock(nro_addr, nro_data.data(), nro_size);
 
+        SHA256Hash hash{};
+        mbedtls_sha256(nro_data.data(), nro_data.size(), hash.data(), 0);
+
+        // NRO Hash is already loaded
+        if (std::any_of(nro.begin(), nro.end(), [&hash](const std::pair<VAddr, NROInfo>& info) {
+                return info.second.hash == hash;
+            })) {
+            LOG_ERROR(Service_LDR, "NRO is already loaded!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_ALREADY_LOADED);
+            return;
+        }
+
+        // NRO Hash is not in any loaded NRR
+        if (!IsValidNROHash(hash)) {
+            LOG_ERROR(Service_LDR,
+                      "NRO hash is not present in any currently loaded NRRs (hash={})!",
+                      Common::HexArrayToString(hash));
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_MISSING_NRR_HASH);
+            return;
+        }
+
+        NROHeader header;
+        std::memcpy(&header, nro_data.data(), sizeof(NROHeader));
+
+        if (!IsValidNRO(header, nro_size, bss_size)) {
+            LOG_ERROR(Service_LDR, "NRO was invalid!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_NRO);
+            return;
+        }
+
         // Load NRO as new executable module
-        const VAddr addr{*Core::CurrentProcess()->VMManager().FindFreeRegion(nro_size + bss_size)};
-        Loader::AppLoader_NRO::LoadNro(nro_data, fmt::format("nro-{:08x}", addr), addr);
+        auto* process = Core::CurrentProcess();
+        auto& vm_manager = process->VMManager();
+        auto map_address = vm_manager.FindFreeRegion(nro_size + bss_size);
+
+        if (!map_address.Succeeded() ||
+            *map_address + nro_size + bss_size > vm_manager.GetAddressSpaceEndAddress()) {
+
+            LOG_ERROR(Service_LDR,
+                      "General error while allocation memory or no available memory to allocate!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_MEMORY_STATE);
+            return;
+        }
+
+        ASSERT(process->MirrorMemory(*map_address, nro_addr, nro_size,
+                                     Kernel::MemoryState::ModuleCodeStatic) == RESULT_SUCCESS);
+        ASSERT(process->UnmapMemory(nro_addr, 0, nro_size) == RESULT_SUCCESS);
+
+        if (bss_size > 0) {
+            ASSERT(process->MirrorMemory(*map_address + nro_size, bss_addr, bss_size,
+                                         Kernel::MemoryState::ModuleCodeStatic) == RESULT_SUCCESS);
+            ASSERT(process->UnmapMemory(bss_addr, 0, bss_size) == RESULT_SUCCESS);
+        }
+
+        vm_manager.ReprotectRange(*map_address, header.text_size,
+                                  Kernel::VMAPermission::ReadExecute);
+        vm_manager.ReprotectRange(*map_address + header.ro_offset, header.ro_size,
+                                  Kernel::VMAPermission::Read);
+        vm_manager.ReprotectRange(*map_address + header.rw_offset, header.rw_size,
+                                  Kernel::VMAPermission::ReadWrite);
 
-        // TODO(bunnei): This is an incomplete implementation. It was tested with Super Mario Party.
-        // It is currently missing:
-        // - Signature checks with LoadNRR
-        // - Checking if a module has already been loaded
-        // - Using/validating BSS, etc. params (these are used from NRO header instead)
-        // - Error checking
-        // - ...Probably other things
+        Core::System::GetInstance().ArmInterface(0).ClearInstructionCache();
+        Core::System::GetInstance().ArmInterface(1).ClearInstructionCache();
+        Core::System::GetInstance().ArmInterface(2).ClearInstructionCache();
+        Core::System::GetInstance().ArmInterface(3).ClearInstructionCache();
+
+        nro.insert_or_assign(*map_address, NROInfo{hash, nro_size + bss_size});
 
         IPC::ResponseBuilder rb{ctx, 4};
         rb.Push(RESULT_SUCCESS);
-        rb.Push(addr);
-        LOG_WARNING(Service_LDR, "(STUBBED) called");
+        rb.Push(*map_address);
+    }
+
+    void UnloadNro(Kernel::HLERequestContext& ctx) {
+        IPC::RequestParser rp{ctx};
+        rp.Skip(2, false);
+        const VAddr mapped_addr{rp.PopRaw<VAddr>()};
+        const VAddr heap_addr{rp.PopRaw<VAddr>()};
+
+        if (!initialized) {
+            LOG_ERROR(Service_LDR, "LDR:RO not initialized before use!");
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_NOT_INITIALIZED);
+            return;
+        }
+
+        if (!Common::Is4KBAligned(mapped_addr) || !Common::Is4KBAligned(heap_addr)) {
+            LOG_ERROR(Service_LDR,
+                      "NRO/BSS Address has invalid alignment (actual nro_addr={:016X}, "
+                      "bss_addr={:016X})!",
+                      mapped_addr, heap_addr);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_ALIGNMENT);
+            return;
+        }
+
+        const auto iter = nro.find(mapped_addr);
+        if (iter == nro.end()) {
+            LOG_ERROR(Service_LDR,
+                      "The NRO attempting to unmap was not mapped or has an invalid address "
+                      "(actual {:016X})!",
+                      mapped_addr);
+            IPC::ResponseBuilder rb{ctx, 2};
+            rb.Push(ERROR_INVALID_NRO_ADDRESS);
+            return;
+        }
+
+        auto* process = Core::CurrentProcess();
+        auto& vm_manager = process->VMManager();
+        const auto& nro_size = iter->second.size;
+
+        ASSERT(process->MirrorMemory(heap_addr, mapped_addr, nro_size,
+                                     Kernel::MemoryState::ModuleCodeStatic) == RESULT_SUCCESS);
+        ASSERT(process->UnmapMemory(mapped_addr, 0, nro_size) == RESULT_SUCCESS);
+
+        Core::System::GetInstance().ArmInterface(0).ClearInstructionCache();
+        Core::System::GetInstance().ArmInterface(1).ClearInstructionCache();
+        Core::System::GetInstance().ArmInterface(2).ClearInstructionCache();
+        Core::System::GetInstance().ArmInterface(3).ClearInstructionCache();
+
+        nro.erase(iter);
+        IPC::ResponseBuilder rb{ctx, 2};
+        rb.Push(RESULT_SUCCESS);
     }
 
     void Initialize(Kernel::HLERequestContext& ctx) {
+        initialized = true;
+
         IPC::ResponseBuilder rb{ctx, 2};
         rb.Push(RESULT_SUCCESS);
         LOG_WARNING(Service_LDR, "(STUBBED) called");
     }
+
+private:
+    using SHA256Hash = std::array<u8, 0x20>;
+
+    struct NROHeader {
+        u32_le entrypoint_insn;
+        u32_le mod_offset;
+        INSERT_PADDING_WORDS(2);
+        u32_le magic;
+        INSERT_PADDING_WORDS(1);
+        u32_le nro_size;
+        INSERT_PADDING_WORDS(1);
+        u32_le text_offset;
+        u32_le text_size;
+        u32_le ro_offset;
+        u32_le ro_size;
+        u32_le rw_offset;
+        u32_le rw_size;
+        u32_le bss_size;
+        INSERT_PADDING_WORDS(1);
+        std::array<u8, 0x20> build_id;
+        INSERT_PADDING_BYTES(0x20);
+    };
+    static_assert(sizeof(NROHeader) == 0x80, "NROHeader has invalid size.");
+
+    struct NRRHeader {
+        u32_le magic;
+        INSERT_PADDING_BYTES(0x1C);
+        u64_le title_id_mask;
+        u64_le title_id_pattern;
+        std::array<u8, 0x100> modulus;
+        std::array<u8, 0x100> signature_1;
+        std::array<u8, 0x100> signature_2;
+        u64_le title_id;
+        u32_le size;
+        INSERT_PADDING_BYTES(4);
+        u32_le hash_offset;
+        u32_le hash_count;
+        INSERT_PADDING_BYTES(8);
+    };
+    static_assert(sizeof(NRRHeader) == 0x350, "NRRHeader has incorrect size.");
+
+    struct NROInfo {
+        SHA256Hash hash;
+        u64 size;
+    };
+
+    bool initialized = false;
+
+    std::map<VAddr, NROInfo> nro;
+    std::map<VAddr, std::vector<SHA256Hash>> nrr;
+
+    bool IsValidNROHash(const SHA256Hash& hash) {
+        return std::any_of(
+            nrr.begin(), nrr.end(), [&hash](const std::pair<VAddr, std::vector<SHA256Hash>>& p) {
+                return std::find(p.second.begin(), p.second.end(), hash) != p.second.end();
+            });
+    }
+
+    static bool IsValidNRO(const NROHeader& header, u64 nro_size, u64 bss_size) {
+        return header.magic == Common::MakeMagic('N', 'R', 'O', '0') &&
+               header.nro_size == nro_size && header.bss_size == bss_size &&
+               header.ro_offset == header.text_offset + header.text_size &&
+               header.rw_offset == header.ro_offset + header.ro_size &&
+               nro_size == header.rw_offset + header.rw_size &&
+               Common::Is4KBAligned(header.text_size) && Common::Is4KBAligned(header.ro_size) &&
+               Common::Is4KBAligned(header.rw_size);
+    }
 };
 
 void InstallInterfaces(SM::ServiceManager& sm) {
diff --git a/src/core/hle/service/ns/pl_u.cpp b/src/core/hle/service/ns/pl_u.cpp
index 44accecb7..1066bf505 100644
--- a/src/core/hle/service/ns/pl_u.cpp
+++ b/src/core/hle/service/ns/pl_u.cpp
@@ -351,6 +351,14 @@ void PL_U::GetSharedFontInOrderOfPriority(Kernel::HLERequestContext& ctx) {
         font_sizes.push_back(region.size);
     }
 
+    // Resize buffers if game requests smaller size output.
+    font_codes.resize(
+        std::min<std::size_t>(font_codes.size(), ctx.GetWriteBufferSize(0) / sizeof(u32)));
+    font_offsets.resize(
+        std::min<std::size_t>(font_offsets.size(), ctx.GetWriteBufferSize(1) / sizeof(u32)));
+    font_sizes.resize(
+        std::min<std::size_t>(font_sizes.size(), ctx.GetWriteBufferSize(2) / sizeof(u32)));
+
     ctx.WriteBuffer(font_codes, 0);
     ctx.WriteBuffer(font_offsets, 1);
     ctx.WriteBuffer(font_sizes, 2);
diff --git a/src/core/hle/service/time/interface.cpp b/src/core/hle/service/time/interface.cpp
index e3cbd7004..b3a196f65 100644
--- a/src/core/hle/service/time/interface.cpp
+++ b/src/core/hle/service/time/interface.cpp
@@ -23,7 +23,8 @@ Time::Time(std::shared_ptr<Module> time, const char* name)
         {300, nullptr, "CalculateMonotonicSystemClockBaseTimePoint"},
         {400, &Time::GetClockSnapshot, "GetClockSnapshot"},
         {401, nullptr, "GetClockSnapshotFromSystemClockContext"},
-        {500, nullptr, "CalculateStandardUserSystemClockDifferenceByUser"},
+        {500, &Time::CalculateStandardUserSystemClockDifferenceByUser,
+         "CalculateStandardUserSystemClockDifferenceByUser"},
         {501, nullptr, "CalculateSpanBetween"},
     };
     RegisterHandlers(functions);
diff --git a/src/core/hle/service/time/time.cpp b/src/core/hle/service/time/time.cpp
index 85e7b1195..e561a0c52 100644
--- a/src/core/hle/service/time/time.cpp
+++ b/src/core/hle/service/time/time.cpp
@@ -299,6 +299,21 @@ void Module::Interface::GetClockSnapshot(Kernel::HLERequestContext& ctx) {
     ctx.WriteBuffer(&clock_snapshot, sizeof(ClockSnapshot));
 }
 
+void Module::Interface::CalculateStandardUserSystemClockDifferenceByUser(
+    Kernel::HLERequestContext& ctx) {
+    LOG_DEBUG(Service_Time, "called");
+
+    IPC::RequestParser rp{ctx};
+    const auto snapshot_a = rp.PopRaw<ClockSnapshot>();
+    const auto snapshot_b = rp.PopRaw<ClockSnapshot>();
+    const u64 difference =
+        snapshot_b.user_clock_context.offset - snapshot_a.user_clock_context.offset;
+
+    IPC::ResponseBuilder rb{ctx, 4};
+    rb.Push(RESULT_SUCCESS);
+    rb.PushRaw<u64>(difference);
+}
+
 Module::Interface::Interface(std::shared_ptr<Module> time, const char* name)
     : ServiceFramework(name), time(std::move(time)) {}
 
diff --git a/src/core/hle/service/time/time.h b/src/core/hle/service/time/time.h
index 77871ae07..ea43fbea7 100644
--- a/src/core/hle/service/time/time.h
+++ b/src/core/hle/service/time/time.h
@@ -84,6 +84,7 @@ public:
         void GetTimeZoneService(Kernel::HLERequestContext& ctx);
         void GetStandardLocalSystemClock(Kernel::HLERequestContext& ctx);
         void GetClockSnapshot(Kernel::HLERequestContext& ctx);
+        void CalculateStandardUserSystemClockDifferenceByUser(Kernel::HLERequestContext& ctx);
 
     protected:
         std::shared_ptr<Module> time;
diff --git a/src/core/hle/service/vi/vi.cpp b/src/core/hle/service/vi/vi.cpp
index d764b2406..d25fdb1fe 100644
--- a/src/core/hle/service/vi/vi.cpp
+++ b/src/core/hle/service/vi/vi.cpp
@@ -237,6 +237,22 @@ private:
     Data data{};
 };
 
+/// Represents a parcel containing one int '0' as its data
+/// Used by DetachBuffer and Disconnect
+class IGBPEmptyResponseParcel : public Parcel {
+protected:
+    void SerializeData() override {
+        Write(data);
+    }
+
+private:
+    struct Data {
+        u32_le unk_0;
+    };
+
+    Data data{};
+};
+
 class IGBPSetPreallocatedBufferRequestParcel : public Parcel {
 public:
     explicit IGBPSetPreallocatedBufferRequestParcel(std::vector<u8> buffer)
@@ -554,6 +570,12 @@ private:
             ctx.WriteBuffer(response.Serialize());
         } else if (transaction == TransactionId::CancelBuffer) {
             LOG_CRITICAL(Service_VI, "(STUBBED) called, transaction=CancelBuffer");
+        } else if (transaction == TransactionId::Disconnect ||
+                   transaction == TransactionId::DetachBuffer) {
+            const auto buffer = ctx.ReadBuffer();
+
+            IGBPEmptyResponseParcel response{};
+            ctx.WriteBuffer(response.Serialize());
         } else {
             ASSERT_MSG(false, "Unimplemented");
         }