1 files changed, 348 insertions, 0 deletions

diff --git a/src/core/loader/ncch.cpp b/src/core/loader/ncch.cpp
new file mode 100644
index 000000000..a01411e11
--- /dev/null
+++ b/src/core/loader/ncch.cpp
@@ -0,0 +1,348 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2
+// Refer to the license.txt file included.
+
+#include "common/file_util.h"
+
+#include "core/loader/ncch.h"
+#include "core/hle/kernel/kernel.h"
+#include "core/mem_map.h"
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+/// NCCH header (Note: "NCCH" appears to be a publically unknown acronym)
+
+struct NCCH_Header {
+    u8 signature[0x100];
+    char magic[4];
+    u32 content_size;
+    u8 partition_id[8];
+    u16 maker_code;
+    u16 version;
+    u8 reserved_0[4];
+    u8 program_id[8];
+    u8 temp_flag;
+    u8 reserved_1[0x2f];
+    u8 product_code[0x10];
+    u8 extended_header_hash[0x20];
+    u32 extended_header_size;
+    u8 reserved_2[4];
+    u8 flags[8];
+    u32 plain_region_offset;
+    u32 plain_region_size;
+    u8 reserved_3[8];
+    u32 exefs_offset;
+    u32 exefs_size;
+    u32 exefs_hash_region_size;
+    u8 reserved_4[4];
+    u32 romfs_offset;
+    u32 romfs_size;
+    u32 romfs_hash_region_size;
+    u8 reserved_5[4];
+    u8 exefs_super_block_hash[0x20];
+    u8 romfs_super_block_hash[0x20];
+};
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// ExeFS (executable file system) headers
+
+typedef struct {
+    char name[8];
+    u32 offset;
+    u32 size;
+} ExeFs_SectionHeader;
+
+typedef struct {
+    ExeFs_SectionHeader section[8];
+    u8 reserved[0x80];
+    u8 hashes[8][0x20];
+} ExeFs_Header;
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// ExHeader (executable file system header) headers
+
+struct ExHeader_SystemInfoFlags{
+    u8 reserved[5];
+    u8 flag;
+    u8 remaster_version[2];
+} exheader_systeminfoflags;
+
+struct ExHeader_CodeSegmentInfo{
+    u32 address;
+    u32 num_max_pages;
+    u32 code_size;
+} exheader_codesegmentinfo;
+
+struct ExHeader_CodeSetInfo {
+    u8 name[8];
+    ExHeader_SystemInfoFlags flags;
+    ExHeader_CodeSegmentInfo text;
+    u8 stacksize[4];
+    ExHeader_CodeSegmentInfo ro;
+    u8 reserved[4];
+    ExHeader_CodeSegmentInfo data;
+    u8 bsssize[4];
+};
+
+struct ExHeader_DependencyList{
+    u8 program_id[0x30][8];
+};
+
+struct ExHeader_SystemInfo{
+    u32 save_data_size;
+    u8 reserved[4];
+    u8 jump_id[8];
+    u8 reserved_2[0x30];
+};
+
+struct ExHeader_StorageInfo{
+    u8 ext_save_data_id[8];
+    u8 system_save_data_id[8];
+    u8 reserved[8];
+    u8 access_info[7];
+    u8 other_attributes;
+};
+
+struct ExHeader_ARM11_SystemLocalCaps{
+    u8 program_id[8];
+    u8 flags[8];
+    u8 resource_limit_descriptor[0x10][2];
+    ExHeader_StorageInfo storage_info;
+    u8 service_access_control[0x20][8];
+    u8 reserved[0x1f];
+    u8 resource_limit_category;
+};
+
+struct ExHeader_ARM11_KernelCaps{
+    u8 descriptors[28][4];
+    u8 reserved[0x10];
+};
+
+struct ExHeader_ARM9_AccessControl{
+    u8 descriptors[15];
+    u8 descversion;
+};
+
+struct ExHeader_Header{
+    ExHeader_CodeSetInfo codeset_info;
+    ExHeader_DependencyList dependency_list;
+    ExHeader_SystemInfo system_info;
+    ExHeader_ARM11_SystemLocalCaps arm11_system_local_caps;
+    ExHeader_ARM11_KernelCaps arm11_kernel_caps;
+    ExHeader_ARM9_AccessControl arm9_access_control;
+    struct {
+        u8 signature[0x100];
+        u8 ncch_public_key_modulus[0x100];
+        ExHeader_ARM11_SystemLocalCaps arm11_system_local_caps;
+        ExHeader_ARM11_KernelCaps arm11_kernel_caps;
+        ExHeader_ARM9_AccessControl arm9_access_control;
+    } access_desc;
+};
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+// Loader namespace
+
+namespace Loader {
+
+const int kExeFs_MaxSections    = 8;        ///< Maximum number of sections (files) in an ExeFs
+const int kExeFs_BlockSize      = 0x200;    ///< Size of ExeFS blocks (in bytes)
+
+/**
+ * Get the decompressed size of an LZSS compressed ExeFS file
+ * @param buffer Buffer of compressed file
+ * @param size Size of compressed buffer
+ * @return Size of decompressed buffer
+ */
+u32 LZSS_GetDecompressedSize(u8* buffer, u32 size) {
+    u32 offset_size = *(u32*)(buffer + size - 4);
+    return offset_size + size;
+}
+
+/**
+ * Decompress ExeFS file (compressed with LZSS)
+ * @param compressed Compressed buffer
+ * @param compressed_size Size of compressed buffer
+ * @param decompressed Decompressed buffer
+ * @param decompressed_size Size of decompressed buffer
+ * @param error_string String populated with error message on failure
+ * @return True on success, otherwise false
+ */
+bool LZSS_Decompress(u8* compressed, u32 compressed_size, u8* decompressed, u32 decompressed_size, 
+    std::string* error_string) {
+    u8* footer = compressed + compressed_size - 8;
+    u32 buffer_top_and_bottom = *(u32*)footer;
+    u32 i, j;
+    u32 out = decompressed_size;
+    u32 index = compressed_size - ((buffer_top_and_bottom >> 24) & 0xFF);
+    u8 control;
+    u32 stop_index = compressed_size - (buffer_top_and_bottom & 0xFFFFFF);
+
+    memset(decompressed, 0, decompressed_size);
+    memcpy(decompressed, compressed, compressed_size);
+
+    while(index > stop_index) {
+        control = compressed[--index];
+
+        for(i = 0; i < 8; i++) {
+            if(index <= stop_index)
+                break;
+            if(index <= 0)
+                break;
+            if(out <= 0)
+                break;
+
+            if(control & 0x80) {
+                if(index < 2) {
+                    *error_string = "Compression out of bounds";
+                    return false;
+                }
+                index -= 2;
+
+                u32 segment_offset = compressed[index] | (compressed[index + 1] << 8);
+                u32 segment_size = ((segment_offset >> 12) & 15) + 3;
+                segment_offset &= 0x0FFF;
+                segment_offset += 2;
+
+                if(out < segment_size) {
+                    *error_string = "Compression out of bounds";
+                    return false;
+                }
+                for(j = 0; j < segment_size; j++) {
+                    u8 data;
+                    if(out + segment_offset >= decompressed_size) {
+                        *error_string = "Compression out of bounds";
+                        return false;
+                    }
+                    data  = decompressed[out + segment_offset];
+                    decompressed[--out] = data;
+                }
+            } else {
+                if(out < 1) {
+                    *error_string = "Compression out of bounds";
+                    return false;
+                }
+                decompressed[--out] = compressed[--index];
+            }
+            control <<= 1;
+        }
+    }
+    return true;
+}
+
+/**
+ * Load a data buffer into memory at the specified address
+ * @param addr Address to load memory into
+ * @param buffer Buffer of data to load into memory
+ * @param size Size of data to load into memory
+ * @todo Perhaps move this code somewhere more generic?
+ */
+void LoadBuffer(const u32 addr, const u8* const buffer, const int size) {
+    u32 *dst = (u32*)Memory::GetPointer(addr);
+    u32 *src = (u32*)buffer;
+    int size_aligned = (size + 3) / 4;
+
+    for (int j = 0; j < size_aligned; j++) {
+        *dst++ = (*src++);
+    }
+    return;
+}
+
+/**
+ * Loads an NCCH file (e.g. from a CCI, or the first NCCH in a CXI)
+ * @param filename String filename of NCCH file
+ * @param error_string Pointer to string to put error message if an error has occurred
+ * @todo Move NCSD parsing out of here and create a separate function for loading these
+ * @return True on success, otherwise false
+ */
+bool Load_NCCH(std::string& filename, std::string* error_string) {
+    INFO_LOG(LOADER, "Loading NCCH file %s...", filename.c_str());
+
+    File::IOFile file(filename, "rb");
+
+    if (file.IsOpen()) {
+        NCCH_Header ncch_header;
+        file.ReadBytes(&ncch_header, sizeof(NCCH_Header));
+
+        // Skip NCSD header and load first NCCH (NCSD is just a container of NCCH files)...
+        int ncch_off = 0; // Offset to NCCH header, can be 0 or after NCSD header
+        if (memcmp(&ncch_header.magic, "NCSD", 4) == 0) {
+            WARN_LOG(LOADER, "Only loading the first (bootable) NCCH within the NCSD file!");
+            ncch_off = 0x4000;
+            file.Seek(ncch_off, 0);
+            file.ReadBytes(&ncch_header, sizeof(NCCH_Header));
+        }
+        // Verify we are loading the correct file type...
+        if (memcmp(&ncch_header.magic, "NCCH", 4) != 0) {
+            *error_string = "Invalid NCCH magic number (likely incorrect file type)";
+            return false;
+        }
+        // Read ExHeader
+        ExHeader_Header exheader_header;
+        file.ReadBytes(&exheader_header, sizeof(ExHeader_Header));
+
+        bool is_compressed = (exheader_header.codeset_info.flags.flag & 1) == 1;
+
+        INFO_LOG(LOADER, "Name:            %s", exheader_header.codeset_info.name);
+        INFO_LOG(LOADER, "Code compressed: %s", is_compressed ? "yes" : "no");
+
+        // Read ExeFS
+        u32 exefs_offset = ncch_header.exefs_offset * kExeFs_BlockSize;
+        u32 exefs_size = ncch_header.exefs_size * kExeFs_BlockSize;
+
+        INFO_LOG(LOADER, "ExeFS offset:    0x%08X", exefs_offset);
+        INFO_LOG(LOADER, "ExeFS size:      0x%08X", exefs_size);
+
+        ExeFs_Header exefs_header;
+        file.Seek(exefs_offset + ncch_off, 0);
+        file.ReadBytes(&exefs_header, sizeof(ExeFs_Header));
+
+        // Iterate through the ExeFs archive until we find the .code file...
+        for (int i = 0; i < kExeFs_MaxSections; i++) {
+            INFO_LOG(LOADER, "ExeFS section %d:", i);
+            INFO_LOG(LOADER, "    name:   %s", exefs_header.section[i].name);
+            INFO_LOG(LOADER, "    offset: 0x%08X", exefs_header.section[i].offset);
+            INFO_LOG(LOADER, "    size:   0x%08X", exefs_header.section[i].size);
+
+            // Load the .code section (executable code)...
+            if (strcmp((char*) exefs_header.section[i].name, ".code") == 0) {
+                file.Seek(exefs_header.section[i].offset + exefs_offset + sizeof(ExeFs_Header) + 
+                    ncch_off, 0);
+
+                u8* buffer = new u8[exefs_header.section[i].size];
+                file.ReadBytes(buffer, exefs_header.section[i].size);
+
+                // Load compressed executable...
+                if (i == 0 && is_compressed) {
+                    u32 decompressed_size = LZSS_GetDecompressedSize(buffer, 
+                        exefs_header.section[i].size);
+                    u8* decompressed_buffer = new u8[decompressed_size];
+
+                    if (!LZSS_Decompress(buffer, exefs_header.section[i].size, decompressed_buffer,
+                        decompressed_size, error_string)) {
+                        return false;
+                    }
+                    // Load .code section into memory...
+                    LoadBuffer(exheader_header.codeset_info.text.address, decompressed_buffer,
+                        decompressed_size);
+
+                    delete[] decompressed_buffer;
+
+                // Load uncompressed executable...
+                } else {
+                    // Load .code section into memory...
+                    LoadBuffer(exheader_header.codeset_info.text.address, buffer, 
+                        exefs_header.section[i].size);
+                }
+                delete[] buffer;
+
+                // Setup kernel emulation to boot .code section...
+                Kernel::LoadExec(exheader_header.codeset_info.text.address);
+
+                // No need to load the other files from ExeFS until we do something with them...
+                return true;
+            }
+        }
+    }
+    return false;
+}
+
+} // namespace Loader