11 files changed, 652 insertions, 9 deletions

diff --git a/src/core/loader/3dsx.cpp b/src/core/loader/3dsx.cpp
index 918038f1e..7b0342cc9 100644
--- a/src/core/loader/3dsx.cpp
+++ b/src/core/loader/3dsx.cpp
@@ -267,15 +267,15 @@ ResultStatus AppLoader_THREEDSX::Load(Kernel::SharedPtr<Kernel::Process>& proces
         return ResultStatus::Error;
     codeset->name = filename;
 
-    process = Kernel::Process::Create(std::move(codeset));
+    process = Kernel::Process::Create("main");
+    process->LoadModule(codeset, codeset->entrypoint);
     process->svc_access_mask.set();
     process->address_mappings = default_address_mappings;
 
     // Attach the default resource limit (APPLICATION) to the process
     process->resource_limit =
         Kernel::ResourceLimit::GetForCategory(Kernel::ResourceLimitCategory::APPLICATION);
-
-    process->Run(48, Kernel::DEFAULT_STACK_SIZE);
+    process->Run(codeset->entrypoint, 48, Kernel::DEFAULT_STACK_SIZE);
 
     Service::FS::RegisterSelfNCCH(*this);
 
diff --git a/src/core/loader/elf.cpp b/src/core/loader/elf.cpp
index e36e42120..9969a8c39 100644
--- a/src/core/loader/elf.cpp
+++ b/src/core/loader/elf.cpp
@@ -364,12 +364,19 @@ SectionID ElfReader::GetSectionByName(const char* name, int firstSection) const
 namespace Loader {
 
 FileType AppLoader_ELF::IdentifyType(FileUtil::IOFile& file) {
-    u32 magic;
+    static constexpr u16 ELF_MACHINE_ARM{0x28};
+
+    u32 magic = 0;
     file.Seek(0, SEEK_SET);
     if (1 != file.ReadArray<u32>(&magic, 1))
         return FileType::Error;
 
-    if (MakeMagic('\x7f', 'E', 'L', 'F') == magic)
+    u16 machine = 0;
+    file.Seek(18, SEEK_SET);
+    if (1 != file.ReadArray<u16>(&machine, 1))
+        return FileType::Error;
+
+    if (MakeMagic('\x7f', 'E', 'L', 'F') == magic && ELF_MACHINE_ARM == machine)
         return FileType::ELF;
 
     return FileType::Error;
@@ -394,7 +401,8 @@ ResultStatus AppLoader_ELF::Load(Kernel::SharedPtr<Kernel::Process>& process) {
     SharedPtr<CodeSet> codeset = elf_reader.LoadInto(Memory::PROCESS_IMAGE_VADDR);
     codeset->name = filename;
 
-    process = Kernel::Process::Create(std::move(codeset));
+    process = Kernel::Process::Create("main");
+    process->LoadModule(codeset, codeset->entrypoint);
     process->svc_access_mask.set();
     process->address_mappings = default_address_mappings;
 
@@ -402,7 +410,7 @@ ResultStatus AppLoader_ELF::Load(Kernel::SharedPtr<Kernel::Process>& process) {
     process->resource_limit =
         Kernel::ResourceLimit::GetForCategory(Kernel::ResourceLimitCategory::APPLICATION);
 
-    process->Run(48, Kernel::DEFAULT_STACK_SIZE);
+    process->Run(codeset->entrypoint, 48, Kernel::DEFAULT_STACK_SIZE);
 
     is_loaded = true;
     return ResultStatus::Success;
diff --git a/src/core/loader/linker.cpp b/src/core/loader/linker.cpp
new file mode 100644
index 000000000..a265b9315
--- /dev/null
+++ b/src/core/loader/linker.cpp
@@ -0,0 +1,151 @@
+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <vector>
+
+#include "common/common_funcs.h"
+#include "common/logging/log.h"
+#include "common/swap.h"
+#include "core/loader/linker.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 Elf64_Rela {
+    u64_le offset;
+    RelocationType type;
+    u32_le symbol;
+    s64_le addend;
+};
+static_assert(sizeof(Elf64_Rela) == 0x18, "Elf64_Rela has incorrect size.");
+
+struct Elf64_Dyn {
+    u64_le tag;
+    u64_le value;
+};
+static_assert(sizeof(Elf64_Dyn) == 0x10, "Elf64_Dyn has incorrect size.");
+
+struct Elf64_Sym {
+    u32_le name;
+    INSERT_PADDING_BYTES(0x2);
+    u16_le shndx;
+    u64_le value;
+    u64_le size;
+};
+static_assert(sizeof(Elf64_Sym) == 0x18, "Elf64_Sym has incorrect size.");
+
+void Linker::WriteRelocations(std::vector<u8>& program_image,
+                                  const std::vector<Symbol>& symbols, u64 relocation_offset,
+                                  u64 size, bool is_jump_relocation, VAddr load_base) {
+    for (u64 i = 0; i < size; i += sizeof(Elf64_Rela)) {
+        Elf64_Rela rela;
+        std::memcpy(&rela, &program_image[relocation_offset + i], sizeof(Elf64_Rela));
+
+        const Symbol& symbol = symbols[rela.symbol];
+        switch (rela.type) {
+        case RelocationType::RELATIVE: {
+            const u64 value = load_base + rela.addend;
+            if (!symbol.name.empty()) {
+                exports[symbol.name] = value;
+            }
+            std::memcpy(&program_image[rela.offset], &value, sizeof(u64));
+            break;
+        }
+        case RelocationType::JUMP_SLOT:
+        case RelocationType::GLOB_DAT:
+            if (!symbol.value) {
+                imports[symbol.name] = {rela.offset + load_base, 0};
+            } else {
+                exports[symbol.name] = symbol.value;
+                std::memcpy(&program_image[rela.offset], &symbol.value, sizeof(u64));
+            }
+            break;
+        case RelocationType::ABS64:
+            if (!symbol.value) {
+                imports[symbol.name] = {rela.offset + load_base, rela.addend};
+            } else {
+                const u64 value = symbol.value + rela.addend;
+                exports[symbol.name] = value;
+                std::memcpy(&program_image[rela.offset], &value, sizeof(u64));
+            }
+            break;
+        default:
+            LOG_CRITICAL(Loader, "Unknown relocation type: %d", rela.type);
+            break;
+        }
+    }
+}
+
+void Linker::Relocate(std::vector<u8>& program_image, u32 dynamic_section_offset,
+                          VAddr load_base) {
+    std::map<u64, u64> dynamic;
+    while (dynamic_section_offset < program_image.size()) {
+        Elf64_Dyn dyn;
+        std::memcpy(&dyn, &program_image[dynamic_section_offset], sizeof(Elf64_Dyn));
+        dynamic_section_offset += sizeof(Elf64_Dyn);
+
+        if (dyn.tag == DT_NULL) {
+            break;
+        }
+        dynamic[dyn.tag] = dyn.value;
+    }
+
+    u64 offset = dynamic[DT_SYMTAB];
+    std::vector<Symbol> symbols;
+    while (offset < program_image.size()) {
+        Elf64_Sym sym;
+        std::memcpy(&sym, &program_image[offset], sizeof(Elf64_Sym));
+        offset += sizeof(Elf64_Sym);
+
+        if (sym.name >= dynamic[DT_STRSZ]) {
+            break;
+        }
+
+        std::string name = reinterpret_cast<char*>(&program_image[dynamic[DT_STRTAB] + sym.name]);
+        if (sym.value) {
+            exports[name] = load_base + sym.value;
+            symbols.emplace_back(std::move(name), load_base + sym.value);
+        } else {
+            symbols.emplace_back(std::move(name), 0);
+        }
+    }
+
+    if (dynamic.find(DT_RELA) != dynamic.end()) {
+        WriteRelocations(program_image, symbols, dynamic[DT_RELA], dynamic[DT_RELASZ], false,
+                         load_base);
+    }
+
+    if (dynamic.find(DT_JMPREL) != dynamic.end()) {
+        WriteRelocations(program_image, symbols, dynamic[DT_JMPREL], dynamic[DT_PLTRELSZ], true,
+                         load_base);
+    }
+}
+
+void Linker::ResolveImports() {
+    // 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());
+        }
+    }
+}
+
+} // namespace Loader
diff --git a/src/core/loader/linker.h b/src/core/loader/linker.h
new file mode 100644
index 000000000..d18155f0d
--- /dev/null
+++ b/src/core/loader/linker.h
@@ -0,0 +1,37 @@
+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <map>
+#include <string>
+#include "common/common_types.h"
+
+namespace Loader {
+
+class Linker {
+protected:
+    struct Symbol {
+        Symbol(std::string&& name, u64 value) : name(std::move(name)), value(value) {}
+        std::string name;
+        u64 value;
+    };
+
+    struct Import {
+        VAddr ea;
+        s64 addend;
+    };
+
+    void WriteRelocations(std::vector<u8>& program_image, const std::vector<Symbol>& symbols,
+                          u64 relocation_offset, u64 size, bool is_jump_relocation,
+                          VAddr load_base);
+    void Relocate(std::vector<u8>& program_image, u32 dynamic_section_offset, VAddr load_base);
+
+    void ResolveImports();
+
+    std::map<std::string, Import> imports;
+    std::map<std::string, VAddr> exports;
+};
+
+} // namespace Loader
diff --git a/src/core/loader/loader.cpp b/src/core/loader/loader.cpp
index be719d74c..73318c584 100644
--- a/src/core/loader/loader.cpp
+++ b/src/core/loader/loader.cpp
@@ -10,6 +10,8 @@
 #include "core/loader/3dsx.h"
 #include "core/loader/elf.h"
 #include "core/loader/ncch.h"
+#include "core/loader/nro.h"
+#include "core/loader/nso.h"
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 
@@ -32,6 +34,8 @@ FileType IdentifyFile(FileUtil::IOFile& file) {
     CHECK_TYPE(THREEDSX)
     CHECK_TYPE(ELF)
     CHECK_TYPE(NCCH)
+    CHECK_TYPE(NSO)
+    CHECK_TYPE(NRO)
 
 #undef CHECK_TYPE
 
@@ -115,6 +119,14 @@ static std::unique_ptr<AppLoader> GetFileLoader(FileUtil::IOFile&& file, FileTyp
     case FileType::CCI:
         return std::make_unique<AppLoader_NCCH>(std::move(file), filepath);
 
+    // NX NSO file format.
+    case FileType::NSO:
+        return std::make_unique<AppLoader_NSO>(std::move(file), filepath);
+
+    // NX NRO file format.
+    case FileType::NRO:
+        return std::make_unique<AppLoader_NRO>(std::move(file), filepath);
+
     default:
         return nullptr;
     }
diff --git a/src/core/loader/loader.h b/src/core/loader/loader.h
index 82b2be6a3..311785d05 100644
--- a/src/core/loader/loader.h
+++ b/src/core/loader/loader.h
@@ -34,6 +34,8 @@ enum class FileType {
     CIA,
     ELF,
     THREEDSX, // 3DSX
+    NSO,
+    NRO,
 };
 
 /**
diff --git a/src/core/loader/ncch.cpp b/src/core/loader/ncch.cpp
index 52686e364..e33a37b2e 100644
--- a/src/core/loader/ncch.cpp
+++ b/src/core/loader/ncch.cpp
@@ -118,7 +118,8 @@ ResultStatus AppLoader_NCCH::LoadExec(Kernel::SharedPtr<Kernel::Process>& proces
         codeset->entrypoint = codeset->code.addr;
         codeset->memory = std::make_shared<std::vector<u8>>(std::move(code));
 
-        process = Kernel::Process::Create(std::move(codeset));
+        process = Kernel::Process::Create("main");
+        process->LoadModule(codeset, codeset->entrypoint);
 
         // Attach a resource limit to the process based on the resource limit category
         process->resource_limit =
@@ -138,7 +139,7 @@ ResultStatus AppLoader_NCCH::LoadExec(Kernel::SharedPtr<Kernel::Process>& proces
 
         s32 priority = overlay_ncch->exheader_header.arm11_system_local_caps.priority;
         u32 stack_size = overlay_ncch->exheader_header.codeset_info.stack_size;
-        process->Run(priority, stack_size);
+        process->Run(codeset->entrypoint, priority, stack_size);
         return ResultStatus::Success;
     }
     return ResultStatus::Error;
diff --git a/src/core/loader/nro.cpp b/src/core/loader/nro.cpp
new file mode 100644
index 000000000..24c2c55a9
--- /dev/null
+++ b/src/core/loader/nro.cpp
@@ -0,0 +1,162 @@
+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include <vector>
+
+#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/nro.h"
+#include "core/memory.h"
+
+namespace Loader {
+
+struct NroSegmentHeader {
+    u32_le offset;
+    u32_le size;
+};
+static_assert(sizeof(NroSegmentHeader) == 0x8, "NroSegmentHeader has incorrect size.");
+
+struct NroHeader {
+    INSERT_PADDING_BYTES(0x4);
+    u32_le module_header_offset;
+    INSERT_PADDING_BYTES(0x8);
+    u32_le magic;
+    INSERT_PADDING_BYTES(0x4);
+    u32_le file_size;
+    INSERT_PADDING_BYTES(0x4);
+    std::array<NroSegmentHeader, 3> segments; // Text, RoData, Data (in that order)
+    u32_le bss_size;
+    INSERT_PADDING_BYTES(0x44);
+};
+static_assert(sizeof(NroHeader) == 0x80, "NroHeader has incorrect size.");
+
+struct ModHeader {
+    u32_le magic;
+    u32_le dynamic_offset;
+    u32_le bss_start_offset;
+    u32_le bss_end_offset;
+    u32_le unwind_start_offset;
+    u32_le unwind_end_offset;
+    u32_le module_offset; // Offset to runtime-generated module object. typically equal to .bss base
+};
+static_assert(sizeof(ModHeader) == 0x1c, "ModHeader has incorrect size.");
+
+FileType AppLoader_NRO::IdentifyType(FileUtil::IOFile& file) {
+    // Read NSO header
+    NroHeader nro_header{};
+    file.Seek(0, SEEK_SET);
+    if (sizeof(NroHeader) != file.ReadBytes(&nro_header, sizeof(NroHeader))) {
+        return FileType::Error;
+    }
+    if (nro_header.magic == MakeMagic('N', 'R', 'O', '0')) {
+        return FileType::NRO;
+    }
+    return FileType::Error;
+}
+
+static constexpr u32 PageAlignSize(u32 size) {
+    return (size + Memory::PAGE_MASK) & ~Memory::PAGE_MASK;
+}
+
+static std::vector<u8> ReadSegment(FileUtil::IOFile& file, const NroSegmentHeader& header) {
+    std::vector<u8> data;
+    data.resize(header.size);
+
+    file.Seek(header.offset + sizeof(NroHeader), SEEK_SET);
+    size_t bytes_read{file.ReadBytes(data.data(), header.size)};
+    if (header.size != PageAlignSize(static_cast<u32>(bytes_read))) {
+        LOG_CRITICAL(Loader, "Failed to read NRO segment bytes", header.size);
+        return {};
+    }
+
+    return data;
+}
+
+bool AppLoader_NRO::LoadNro(const std::string& path, VAddr load_base) {
+    FileUtil::IOFile file(path, "rb");
+    if (!file.IsOpen()) {
+        return {};
+    }
+
+    // Read NSO header
+    NroHeader nro_header{};
+    file.Seek(0, SEEK_SET);
+    if (sizeof(NroHeader) != file.ReadBytes(&nro_header, sizeof(NroHeader))) {
+        return {};
+    }
+    if (nro_header.magic != MakeMagic('N', 'R', 'O', '0')) {
+        return {};
+    }
+
+    // Build program image
+    Kernel::SharedPtr<Kernel::CodeSet> codeset = Kernel::CodeSet::Create("", 0);
+    std::vector<u8> program_image;
+    program_image.resize(PageAlignSize(nro_header.file_size + nro_header.bss_size));
+    file.Seek(0, SEEK_SET);
+    file.ReadBytes(program_image.data(), nro_header.file_size);
+
+    for (int i = 0; i < nro_header.segments.size(); ++i) {
+        codeset->segments[i].addr = nro_header.segments[i].offset;
+        codeset->segments[i].offset = nro_header.segments[i].offset;
+        codeset->segments[i].size = PageAlignSize(nro_header.segments[i].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() + nro_header.module_header_offset,
+                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));
+
+    // 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(program_image, nro_header.module_header_offset + mod_header.dynamic_offset,
+                 load_base);
+    }
+
+    // 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);
+
+    return true;
+}
+
+ResultStatus AppLoader_NRO::Load(Kernel::SharedPtr<Kernel::Process>& process) {
+    if (is_loaded) {
+        return ResultStatus::ErrorAlreadyLoaded;
+    }
+    if (!file.IsOpen()) {
+        return ResultStatus::Error;
+    }
+
+    // Load and relocate "main" and "sdk" NSO
+    static constexpr VAddr base_addr{Memory::PROCESS_IMAGE_VADDR};
+    process = Kernel::Process::Create("main");
+    if (!LoadNro(filepath, base_addr)) {
+        return ResultStatus::ErrorInvalidFormat;
+    }
+
+    process->svc_access_mask.set();
+    process->address_mappings = default_address_mappings;
+    process->resource_limit =
+        Kernel::ResourceLimit::GetForCategory(Kernel::ResourceLimitCategory::APPLICATION);
+    process->Run(base_addr, 48, Kernel::DEFAULT_STACK_SIZE);
+
+    ResolveImports();
+
+    is_loaded = true;
+    return ResultStatus::Success;
+}
+
+} // namespace Loader
diff --git a/src/core/loader/nro.h b/src/core/loader/nro.h
new file mode 100644
index 000000000..c85768c5b
--- /dev/null
+++ b/src/core/loader/nro.h
@@ -0,0 +1,42 @@
+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <map>
+#include <string>
+#include "common/common_types.h"
+#include "common/file_util.h"
+#include "core/hle/kernel/kernel.h"
+#include "core/loader/linker.h"
+#include "core/loader/loader.h"
+
+namespace Loader {
+
+/// Loads an NRO file
+class AppLoader_NRO final : public AppLoader, Linker {
+public:
+    AppLoader_NRO(FileUtil::IOFile&& file, std::string filepath)
+        : AppLoader(std::move(file)), filepath(std::move(filepath)) {}
+
+    /**
+     * Returns the type of the file
+     * @param file FileUtil::IOFile open file
+     * @return FileType found, or FileType::Error if this loader doesn't know it
+     */
+    static FileType IdentifyType(FileUtil::IOFile& file);
+
+    FileType GetFileType() override {
+        return IdentifyType(file);
+    }
+
+    ResultStatus Load(Kernel::SharedPtr<Kernel::Process>& process) override;
+
+private:
+    bool LoadNro(const std::string& path, VAddr load_base);
+
+    std::string filepath;
+};
+
+} // namespace Loader
diff --git a/src/core/loader/nso.cpp b/src/core/loader/nso.cpp
new file mode 100644
index 000000000..b1b57d0c0
--- /dev/null
+++ b/src/core/loader/nso.cpp
@@ -0,0 +1,185 @@
+// 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 {
+
+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 {
+    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) == 0x1c, "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(
+        reinterpret_cast<const char*>(compressed_data.data()),
+        reinterpret_cast<char*>(uncompressed_data.data()), compressed_size, header.size);
+
+    ASSERT_MSG(bytes_uncompressed == header.size && bytes_uncompressed == uncompressed_data.size(),
+               "%d != %d != %d", bytes_uncompressed, header.size, uncompressed_data.size());
+
+    return uncompressed_data;
+}
+
+static constexpr u32 PageAlignSize(u32 size) {
+    return (size + Memory::PAGE_MASK) & ~Memory::PAGE_MASK;
+}
+
+VAddr AppLoader_NSO::LoadNso(const std::string& path, VAddr load_base, bool relocate) {
+    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()));
+    }
+
+    // MOD header pointer is at .text offset + 4
+    u32 module_offset;
+    std::memcpy(&module_offset, program_image.data() + 4, sizeof(u32));
+
+    // 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() + module_offset, 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;
+    }
+    const u32 image_size{PageAlignSize(static_cast<u32>(program_image.size()) + bss_size)};
+    program_image.resize(image_size);
+
+    // 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) {
+        Relocate(program_image, module_offset + mod_header.dynamic_offset, load_base);
+    }
+
+    // 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);
+
+    return load_base + image_size;
+}
+
+ResultStatus AppLoader_NSO::Load(Kernel::SharedPtr<Kernel::Process>& process) {
+    if (is_loaded) {
+        return ResultStatus::ErrorAlreadyLoaded;
+    }
+    if (!file.IsOpen()) {
+        return ResultStatus::Error;
+    }
+
+    // Load and relocate "rtld" NSO
+    static constexpr VAddr base_addr{Memory::PROCESS_IMAGE_VADDR};
+    process = Kernel::Process::Create("main");
+    VAddr next_base_addr{LoadNso(filepath, base_addr)};
+    if (!next_base_addr) {
+        return ResultStatus::ErrorInvalidFormat;
+    }
+
+    // Load and relocate remaining submodules
+    for (const auto& module_name : {"main", "sdk", "subsdk0", "subsdk1"}) {
+        const std::string module_path =
+            filepath.substr(0, filepath.find_last_of("/\\")) + "/" + module_name;
+        next_base_addr = LoadNso(module_path, next_base_addr);
+        if (!next_base_addr) {
+            LOG_WARNING(Loader, "failed to find load module: %s", module_name);
+        }
+    }
+
+    process->svc_access_mask.set();
+    process->address_mappings = default_address_mappings;
+    process->resource_limit =
+        Kernel::ResourceLimit::GetForCategory(Kernel::ResourceLimitCategory::APPLICATION);
+    process->Run(base_addr, 48, Kernel::DEFAULT_STACK_SIZE);
+
+    ResolveImports();
+
+    is_loaded = true;
+    return ResultStatus::Success;
+}
+
+} // namespace Loader
diff --git a/src/core/loader/nso.h b/src/core/loader/nso.h
new file mode 100644
index 000000000..b6b86c209
--- /dev/null
+++ b/src/core/loader/nso.h
@@ -0,0 +1,43 @@
+// Copyright 2017 Citra Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <map>
+#include <string>
+#include "common/common_types.h"
+#include "common/file_util.h"
+#include "core/hle/kernel/kernel.h"
+#include "core/loader/linker.h"
+#include "core/loader/loader.h"
+
+namespace Loader {
+
+/// Loads an NSO file
+class AppLoader_NSO final : public AppLoader, Linker {
+public:
+    AppLoader_NSO(FileUtil::IOFile&& file, std::string filepath)
+        : AppLoader(std::move(file)), filepath(std::move(filepath)) {
+    }
+
+    /**
+     * Returns the type of the file
+     * @param file FileUtil::IOFile open file
+     * @return FileType found, or FileType::Error if this loader doesn't know it
+     */
+    static FileType IdentifyType(FileUtil::IOFile& file);
+
+    FileType GetFileType() override {
+        return IdentifyType(file);
+    }
+
+    ResultStatus Load(Kernel::SharedPtr<Kernel::Process>& process) override;
+
+private:
+    VAddr LoadNso(const std::string& path, VAddr load_base, bool relocate = false);
+
+    std::string filepath;
+};
+
+} // namespace Loader