10 files changed, 101 insertions, 44 deletions

diff --git a/src/core/loader/deconstructed_rom_directory.cpp b/src/core/loader/deconstructed_rom_directory.cpp
index 1ae4bb656..2b8f78136 100644
--- a/src/core/loader/deconstructed_rom_directory.cpp
+++ b/src/core/loader/deconstructed_rom_directory.cpp
@@ -9,6 +9,7 @@
 #include "core/core.h"
 #include "core/file_sys/content_archive.h"
 #include "core/file_sys/control_metadata.h"
+#include "core/file_sys/patch_manager.h"
 #include "core/file_sys/romfs_factory.h"
 #include "core/gdbstub/gdbstub.h"
 #include "core/hle/kernel/kernel.h"
@@ -21,10 +22,19 @@
 
 namespace Loader {
 
-AppLoader_DeconstructedRomDirectory::AppLoader_DeconstructedRomDirectory(FileSys::VirtualFile file_)
-    : AppLoader(std::move(file_)) {
+AppLoader_DeconstructedRomDirectory::AppLoader_DeconstructedRomDirectory(FileSys::VirtualFile file_,
+                                                                         bool override_update)
+    : AppLoader(std::move(file_)), override_update(override_update) {
     const auto dir = file->GetContainingDirectory();
 
+    // Title ID
+    const auto npdm = dir->GetFile("main.npdm");
+    if (npdm != nullptr) {
+        const auto res = metadata.Load(npdm);
+        if (res == ResultStatus::Success)
+            title_id = metadata.GetTitleID();
+    }
+
     // Icon
     FileSys::VirtualFile icon_file = nullptr;
     for (const auto& language : FileSys::LANGUAGE_NAMES) {
@@ -66,8 +76,9 @@ AppLoader_DeconstructedRomDirectory::AppLoader_DeconstructedRomDirectory(FileSys
 }
 
 AppLoader_DeconstructedRomDirectory::AppLoader_DeconstructedRomDirectory(
-    FileSys::VirtualDir directory)
-    : AppLoader(directory->GetFile("main")), dir(std::move(directory)) {}
+    FileSys::VirtualDir directory, bool override_update)
+    : AppLoader(directory->GetFile("main")), dir(std::move(directory)),
+      override_update(override_update) {}
 
 FileType AppLoader_DeconstructedRomDirectory::IdentifyType(const FileSys::VirtualFile& file) {
     if (FileSys::IsDirectoryExeFS(file->GetContainingDirectory())) {
@@ -89,7 +100,8 @@ ResultStatus AppLoader_DeconstructedRomDirectory::Load(
         dir = file->GetContainingDirectory();
     }
 
-    const FileSys::VirtualFile npdm = dir->GetFile("main.npdm");
+    // Read meta to determine title ID
+    FileSys::VirtualFile npdm = dir->GetFile("main.npdm");
     if (npdm == nullptr)
         return ResultStatus::ErrorMissingNPDM;
 
@@ -97,6 +109,21 @@ ResultStatus AppLoader_DeconstructedRomDirectory::Load(
     if (result != ResultStatus::Success) {
         return result;
     }
+
+    if (override_update) {
+        const FileSys::PatchManager patch_manager(metadata.GetTitleID());
+        dir = patch_manager.PatchExeFS(dir);
+    }
+
+    // Reread in case PatchExeFS affected the main.npdm
+    npdm = dir->GetFile("main.npdm");
+    if (npdm == nullptr)
+        return ResultStatus::ErrorMissingNPDM;
+
+    ResultStatus result2 = metadata.Load(npdm);
+    if (result2 != ResultStatus::Success) {
+        return result2;
+    }
     metadata.Print();
 
     const FileSys::ProgramAddressSpaceType arch_bits{metadata.GetAddressSpaceType()};
@@ -119,7 +146,6 @@ ResultStatus AppLoader_DeconstructedRomDirectory::Load(
     }
 
     auto& kernel = Core::System::GetInstance().Kernel();
-    title_id = metadata.GetTitleID();
     process->program_id = metadata.GetTitleID();
     process->svc_access_mask.set();
     process->resource_limit =
@@ -170,4 +196,8 @@ ResultStatus AppLoader_DeconstructedRomDirectory::ReadTitle(std::string& title)
     return ResultStatus::Success;
 }
 
+bool AppLoader_DeconstructedRomDirectory::IsRomFSUpdatable() const {
+    return false;
+}
+
 } // namespace Loader
diff --git a/src/core/loader/deconstructed_rom_directory.h b/src/core/loader/deconstructed_rom_directory.h
index b20804f75..8a0dc1b1e 100644
--- a/src/core/loader/deconstructed_rom_directory.h
+++ b/src/core/loader/deconstructed_rom_directory.h
@@ -20,10 +20,12 @@ namespace Loader {
  */
 class AppLoader_DeconstructedRomDirectory final : public AppLoader {
 public:
-    explicit AppLoader_DeconstructedRomDirectory(FileSys::VirtualFile main_file);
+    explicit AppLoader_DeconstructedRomDirectory(FileSys::VirtualFile main_file,
+                                                 bool override_update = false);
 
     // Overload to accept exefs directory. Must contain 'main' and 'main.npdm'
-    explicit AppLoader_DeconstructedRomDirectory(FileSys::VirtualDir directory);
+    explicit AppLoader_DeconstructedRomDirectory(FileSys::VirtualDir directory,
+                                                 bool override_update = false);
 
     /**
      * Returns the type of the file
@@ -42,6 +44,7 @@ public:
     ResultStatus ReadIcon(std::vector<u8>& buffer) override;
     ResultStatus ReadProgramId(u64& out_program_id) override;
     ResultStatus ReadTitle(std::string& title) override;
+    bool IsRomFSUpdatable() const override;
 
 private:
     FileSys::ProgramMetadata metadata;
@@ -51,6 +54,7 @@ private:
     std::vector<u8> icon_data;
     std::string name;
     u64 title_id{};
+    bool override_update;
 };
 
 } // namespace Loader
diff --git a/src/core/loader/loader.cpp b/src/core/loader/loader.cpp
index 446adf557..fa43a2650 100644
--- a/src/core/loader/loader.cpp
+++ b/src/core/loader/loader.cpp
@@ -93,7 +93,7 @@ std::string GetFileTypeString(FileType type) {
     return "unknown";
 }
 
-constexpr std::array<const char*, 50> RESULT_MESSAGES{
+constexpr std::array<const char*, 58> RESULT_MESSAGES{
     "The operation completed successfully.",
     "The loader requested to load is already loaded.",
     "The operation is not implemented.",
@@ -143,7 +143,16 @@ constexpr std::array<const char*, 50> RESULT_MESSAGES{
     "The AES Key Generation Source could not be found.",
     "The SD Save Key Source could not be found.",
     "The SD NCA Key Source could not be found.",
-    "The NSP file is missing a Program-type NCA."};
+    "The NSP file is missing a Program-type NCA.",
+    "The BKTR-type NCA has a bad BKTR header.",
+    "The BKTR Subsection entry is not located immediately after the Relocation entry.",
+    "The BKTR Subsection entry is not at the end of the media block.",
+    "The BKTR-type NCA has a bad Relocation block.",
+    "The BKTR-type NCA has a bad Subsection block.",
+    "The BKTR-type NCA has a bad Relocation bucket.",
+    "The BKTR-type NCA has a bad Subsection bucket.",
+    "The BKTR-type NCA is missing the base RomFS.",
+};
 
 std::ostream& operator<<(std::ostream& os, ResultStatus status) {
     os << RESULT_MESSAGES.at(static_cast<size_t>(status));
diff --git a/src/core/loader/loader.h b/src/core/loader/loader.h
index be66b2257..843c4bb91 100644
--- a/src/core/loader/loader.h
+++ b/src/core/loader/loader.h
@@ -107,6 +107,14 @@ enum class ResultStatus : u16 {
     ErrorMissingSDSaveKeySource,
     ErrorMissingSDNCAKeySource,
     ErrorNSPMissingProgramNCA,
+    ErrorBadBKTRHeader,
+    ErrorBKTRSubsectionNotAfterRelocation,
+    ErrorBKTRSubsectionNotAtEnd,
+    ErrorBadRelocationBlock,
+    ErrorBadSubsectionBlock,
+    ErrorBadRelocationBuckets,
+    ErrorBadSubsectionBuckets,
+    ErrorMissingBKTRBaseRomFS,
 };
 
 std::ostream& operator<<(std::ostream& os, ResultStatus status);
@@ -197,13 +205,22 @@ public:
     }
 
     /**
-     * Get the update RomFS of the application
-     * Since the RomFS can be huge, we return a file reference instead of copying to a buffer
-     * @param file The file containing the RomFS
-     * @return ResultStatus result of function
+     * Get whether or not updates can be applied to the RomFS.
+     * By default, this is true, however for formats where it cannot be guaranteed that the RomFS is
+     * the base game it should be set to false.
+     * @return bool whether or not updatable.
      */
-    virtual ResultStatus ReadUpdateRomFS(FileSys::VirtualFile& file) {
-        return ResultStatus::ErrorNotImplemented;
+    virtual bool IsRomFSUpdatable() const {
+        return true;
+    }
+
+    /**
+     * Gets the difference between the start of the IVFC header and the start of level 6 (RomFS)
+     * data. Needed for bktr patching.
+     * @return IVFC offset for romfs.
+     */
+    virtual u64 ReadRomFSIVFCOffset() const {
+        return 0;
     }
 
     /**
diff --git a/src/core/loader/nca.cpp b/src/core/loader/nca.cpp
index c036a8a1c..6aaffae59 100644
--- a/src/core/loader/nca.cpp
+++ b/src/core/loader/nca.cpp
@@ -48,7 +48,7 @@ ResultStatus AppLoader_NCA::Load(Kernel::SharedPtr<Kernel::Process>& process) {
     if (exefs == nullptr)
         return ResultStatus::ErrorNoExeFS;
 
-    directory_loader = std::make_unique<AppLoader_DeconstructedRomDirectory>(exefs);
+    directory_loader = std::make_unique<AppLoader_DeconstructedRomDirectory>(exefs, true);
 
     const auto load_result = directory_loader->Load(process);
     if (load_result != ResultStatus::Success)
@@ -71,6 +71,12 @@ ResultStatus AppLoader_NCA::ReadRomFS(FileSys::VirtualFile& dir) {
     return ResultStatus::Success;
 }
 
+u64 AppLoader_NCA::ReadRomFSIVFCOffset() const {
+    if (nca == nullptr)
+        return 0;
+    return nca->GetBaseIVFCOffset();
+}
+
 ResultStatus AppLoader_NCA::ReadProgramId(u64& out_program_id) {
     if (nca == nullptr || nca->GetStatus() != ResultStatus::Success)
         return ResultStatus::ErrorNotInitialized;
diff --git a/src/core/loader/nca.h b/src/core/loader/nca.h
index 326f84857..10be197c4 100644
--- a/src/core/loader/nca.h
+++ b/src/core/loader/nca.h
@@ -37,6 +37,7 @@ public:
     ResultStatus Load(Kernel::SharedPtr<Kernel::Process>& process) override;
 
     ResultStatus ReadRomFS(FileSys::VirtualFile& dir) override;
+    u64 ReadRomFSIVFCOffset() const override;
     ResultStatus ReadProgramId(u64& out_program_id) override;
 
 private:
diff --git a/src/core/loader/nro.cpp b/src/core/loader/nro.cpp
index 77026b850..bb89a9da3 100644
--- a/src/core/loader/nro.cpp
+++ b/src/core/loader/nro.cpp
@@ -232,4 +232,9 @@ ResultStatus AppLoader_NRO::ReadTitle(std::string& title) {
     title = nacp->GetApplicationName();
     return ResultStatus::Success;
 }
+
+bool AppLoader_NRO::IsRomFSUpdatable() const {
+    return false;
+}
+
 } // namespace Loader
diff --git a/src/core/loader/nro.h b/src/core/loader/nro.h
index bb01c9e25..96d2de305 100644
--- a/src/core/loader/nro.h
+++ b/src/core/loader/nro.h
@@ -39,6 +39,7 @@ public:
     ResultStatus ReadProgramId(u64& out_program_id) override;
     ResultStatus ReadRomFS(FileSys::VirtualFile& dir) override;
     ResultStatus ReadTitle(std::string& title) override;
+    bool IsRomFSUpdatable() const override;
 
 private:
     bool LoadNro(FileSys::VirtualFile file, VAddr load_base);
diff --git a/src/core/loader/nsp.cpp b/src/core/loader/nsp.cpp
index 7c06239f2..291a9876d 100644
--- a/src/core/loader/nsp.cpp
+++ b/src/core/loader/nsp.cpp
@@ -9,6 +9,8 @@
 #include "core/file_sys/content_archive.h"
 #include "core/file_sys/control_metadata.h"
 #include "core/file_sys/nca_metadata.h"
+#include "core/file_sys/patch_manager.h"
+#include "core/file_sys/registered_cache.h"
 #include "core/file_sys/romfs.h"
 #include "core/file_sys/submission_package.h"
 #include "core/hle/kernel/process.h"
@@ -28,24 +30,12 @@ AppLoader_NSP::AppLoader_NSP(FileSys::VirtualFile file)
         return;
 
     const auto control_nca =
-        nsp->GetNCA(nsp->GetFirstTitleID(), FileSys::ContentRecordType::Control);
+        nsp->GetNCA(nsp->GetProgramTitleID(), FileSys::ContentRecordType::Control);
     if (control_nca == nullptr || control_nca->GetStatus() != ResultStatus::Success)
         return;
 
-    const auto romfs = FileSys::ExtractRomFS(control_nca->GetRomFS());
-    if (romfs == nullptr)
-        return;
-
-    for (const auto& language : FileSys::LANGUAGE_NAMES) {
-        icon_file = romfs->GetFile("icon_" + std::string(language) + ".dat");
-        if (icon_file != nullptr)
-            break;
-    }
-
-    const auto nacp_raw = romfs->GetFile("control.nacp");
-    if (nacp_raw == nullptr)
-        return;
-    nacp_file = std::make_shared<FileSys::NACP>(nacp_raw);
+    std::tie(nacp_file, icon_file) =
+        FileSys::PatchManager(nsp->GetProgramTitleID()).ParseControlNCA(control_nca);
 }
 
 AppLoader_NSP::~AppLoader_NSP() = default;
diff --git a/src/core/loader/xci.cpp b/src/core/loader/xci.cpp
index 75b998faa..16509229f 100644
--- a/src/core/loader/xci.cpp
+++ b/src/core/loader/xci.cpp
@@ -8,7 +8,9 @@
 #include "core/file_sys/card_image.h"
 #include "core/file_sys/content_archive.h"
 #include "core/file_sys/control_metadata.h"
+#include "core/file_sys/patch_manager.h"
 #include "core/file_sys/romfs.h"
+#include "core/file_sys/submission_package.h"
 #include "core/hle/kernel/process.h"
 #include "core/loader/nca.h"
 #include "core/loader/xci.h"
@@ -20,21 +22,13 @@ AppLoader_XCI::AppLoader_XCI(FileSys::VirtualFile file)
       nca_loader(std::make_unique<AppLoader_NCA>(xci->GetProgramNCAFile())) {
     if (xci->GetStatus() != ResultStatus::Success)
         return;
+
     const auto control_nca = xci->GetNCAByType(FileSys::NCAContentType::Control);
     if (control_nca == nullptr || control_nca->GetStatus() != ResultStatus::Success)
         return;
-    const auto romfs = FileSys::ExtractRomFS(control_nca->GetRomFS());
-    if (romfs == nullptr)
-        return;
-    for (const auto& language : FileSys::LANGUAGE_NAMES) {
-        icon_file = romfs->GetFile("icon_" + std::string(language) + ".dat");
-        if (icon_file != nullptr)
-            break;
-    }
-    const auto nacp_raw = romfs->GetFile("control.nacp");
-    if (nacp_raw == nullptr)
-        return;
-    nacp_file = std::make_shared<FileSys::NACP>(nacp_raw);
+
+    std::tie(nacp_file, icon_file) =
+        FileSys::PatchManager(xci->GetProgramTitleID()).ParseControlNCA(control_nca);
 }
 
 AppLoader_XCI::~AppLoader_XCI() = default;