From 08aaa3350066b5d506368d18dddba3f829c85b7a Mon Sep 17 00:00:00 2001 From: Emmanuel Gil Peyrot Date: Wed, 7 Jan 2015 01:01:19 +0000 Subject: Loader: Clean up the NCCH AppLoader. --- src/core/loader/ncch.cpp | 99 +++++++++++++++++++++++------------------------- 1 file changed, 48 insertions(+), 51 deletions(-) diff --git a/src/core/loader/ncch.cpp b/src/core/loader/ncch.cpp index d6eb549b7..aaaa4d650 100644 --- a/src/core/loader/ncch.cpp +++ b/src/core/loader/ncch.cpp @@ -13,8 +13,8 @@ namespace Loader { -static const int kMaxSections = 8; ///< Maximum number of sections (files) in an ExeFs -static const int kBlockSize = 0x200; ///< Size of ExeFS blocks (in bytes) +static const int kMaxSections = 8; ///< Maximum number of sections (files) in an ExeFs +static const int kBlockSize = 0x200; ///< Size of ExeFS blocks (in bytes) /** * Get the decompressed size of an LZSS compressed ExeFS file @@ -22,7 +22,7 @@ static const int kBlockSize = 0x200; ///< Size of ExeFS blocks (in bytes) * @param size Size of compressed buffer * @return Size of decompressed buffer */ -static u32 LZSS_GetDecompressedSize(u8* buffer, u32 size) { +static u32 LZSS_GetDecompressedSize(const u8* buffer, u32 size) { u32 offset_size = *(u32*)(buffer + size - 4); return offset_size + size; } @@ -35,9 +35,9 @@ static u32 LZSS_GetDecompressedSize(u8* buffer, u32 size) { * @param decompressed_size Size of decompressed buffer * @return True on success, otherwise false */ -static bool LZSS_Decompress(u8* compressed, u32 compressed_size, u8* decompressed, u32 decompressed_size) { - u8* footer = compressed + compressed_size - 8; - u32 buffer_top_and_bottom = *(u32*)footer; +static bool LZSS_Decompress(const u8* compressed, u32 compressed_size, u8* decompressed, u32 decompressed_size) { + const u8* footer = compressed + compressed_size - 8; + u32 buffer_top_and_bottom = *reinterpret_cast(footer); u32 out = decompressed_size; u32 index = compressed_size - ((buffer_top_and_bottom >> 24) & 0xFF); u32 stop_index = compressed_size - (buffer_top_and_bottom & 0xFFFFFF); @@ -45,22 +45,21 @@ static bool LZSS_Decompress(u8* compressed, u32 compressed_size, u8* decompresse memset(decompressed, 0, decompressed_size); memcpy(decompressed, compressed, compressed_size); - while(index > stop_index) { + while (index > stop_index) { u8 control = compressed[--index]; - for(u32 i = 0; i < 8; i++) { - if(index <= stop_index) + for (unsigned i = 0; i < 8; i++) { + if (index <= stop_index) break; - if(index <= 0) + if (index <= 0) break; - if(out <= 0) + if (out <= 0) break; - if(control & 0x80) { + if (control & 0x80) { // Check if compression is out of bounds - if(index < 2) { + if (index < 2) return false; - } index -= 2; u32 segment_offset = compressed[index] | (compressed[index + 1] << 8); @@ -69,23 +68,21 @@ static bool LZSS_Decompress(u8* compressed, u32 compressed_size, u8* decompresse segment_offset += 2; // Check if compression is out of bounds - if(out < segment_size) { + if (out < segment_size) return false; - } - for(u32 j = 0; j < segment_size; j++) { + + for (unsigned j = 0; j < segment_size; j++) { // Check if compression is out of bounds - if(out + segment_offset >= decompressed_size) { + if (out + segment_offset >= decompressed_size) return false; - } - u8 data = decompressed[out + segment_offset]; + u8 data = decompressed[out + segment_offset]; decompressed[--out] = data; } } else { // Check if compression is out of bounds - if(out < 1) { + if (out < 1) return false; - } decompressed[--out] = compressed[--index]; } control <<= 1; @@ -126,46 +123,44 @@ ResultStatus AppLoader_NCCH::LoadExec() const { } ResultStatus AppLoader_NCCH::LoadSectionExeFS(const char* name, std::vector& buffer) const { - // Iterate through the ExeFs archive until we find the .code file... if (!file->IsOpen()) return ResultStatus::Error; LOG_DEBUG(Loader, "%d sections:", kMaxSections); - for (int i = 0; i < kMaxSections; i++) { + // Iterate through the ExeFs archive until we find the .code file... + for (unsigned section_number = 0; section_number < kMaxSections; section_number++) { + const auto& section = exefs_header.section[section_number]; + // Load the specified section... - if (strcmp((const char*)exefs_header.section[i].name, name) == 0) { - LOG_DEBUG(Loader, "%d - offset: 0x%08X, size: 0x%08X, name: %s", i, - exefs_header.section[i].offset, exefs_header.section[i].size, - exefs_header.section[i].name); + if (strcmp(section.name, name) == 0) { + LOG_DEBUG(Loader, "%d - offset: 0x%08X, size: 0x%08X, name: %s", section_number, + section.offset, section.size, section.name); - s64 section_offset = (exefs_header.section[i].offset + exefs_offset + - sizeof(ExeFs_Header)+ncch_offset); + s64 section_offset = (section.offset + exefs_offset + sizeof(ExeFs_Header) + ncch_offset); file->Seek(section_offset, SEEK_SET); - // Section is compressed... - if (i == 0 && is_compressed) { - // Read compressed .code section... + if (is_compressed) { + // Section is compressed, read compressed .code section... std::unique_ptr temp_buffer; try { - temp_buffer.reset(new u8[exefs_header.section[i].size]); + temp_buffer.reset(new u8[section.size]); } catch (std::bad_alloc&) { return ResultStatus::ErrorMemoryAllocationFailed; } - file->ReadBytes(&temp_buffer[0], exefs_header.section[i].size); + + if (file->ReadBytes(&temp_buffer[0], section.size) != section.size) + return ResultStatus::Error; // Decompress .code section... - u32 decompressed_size = LZSS_GetDecompressedSize(&temp_buffer[0], - exefs_header.section[i].size); + u32 decompressed_size = LZSS_GetDecompressedSize(&temp_buffer[0], section.size); buffer.resize(decompressed_size); - if (!LZSS_Decompress(&temp_buffer[0], exefs_header.section[i].size, &buffer[0], - decompressed_size)) { + if (!LZSS_Decompress(&temp_buffer[0], section.size, &buffer[0], decompressed_size)) return ResultStatus::ErrorInvalidFormat; - } + } else { // Section is uncompressed... - } - else { - buffer.resize(exefs_header.section[i].size); - file->ReadBytes(&buffer[0], exefs_header.section[i].size); + buffer.resize(section.size); + if (file->ReadBytes(&buffer[0], section.size) != section.size) + return ResultStatus::Error; } return ResultStatus::Success; } @@ -183,7 +178,8 @@ ResultStatus AppLoader_NCCH::Load() { // Reset read pointer in case this file has been read before. file->Seek(0, SEEK_SET); - file->ReadBytes(&ncch_header, sizeof(NCCH_Header)); + if (file->ReadBytes(&ncch_header, sizeof(NCCH_Header)) != sizeof(NCCH_Header)) + return ResultStatus::Error; // Skip NCSD header and load first NCCH (NCSD is just a container of NCCH files)... if (MakeMagic('N', 'C', 'S', 'D') == ncch_header.magic) { @@ -199,7 +195,8 @@ ResultStatus AppLoader_NCCH::Load() { // Read ExHeader... - file->ReadBytes(&exheader_header, sizeof(ExHeader_Header)); + if (file->ReadBytes(&exheader_header, sizeof(ExHeader_Header)) != sizeof(ExHeader_Header)) + return ResultStatus::Error; is_compressed = (exheader_header.codeset_info.flags.flag & 1) == 1; entry_point = exheader_header.codeset_info.text.address; @@ -217,13 +214,12 @@ ResultStatus AppLoader_NCCH::Load() { LOG_DEBUG(Loader, "ExeFS size: 0x%08X", exefs_size); file->Seek(exefs_offset + ncch_offset, SEEK_SET); - file->ReadBytes(&exefs_header, sizeof(ExeFs_Header)); - - LoadExec(); // Load the executable into memory for booting + if (file->ReadBytes(&exefs_header, sizeof(ExeFs_Header)) != sizeof(ExeFs_Header)) + return ResultStatus::Error; is_loaded = true; // Set state to loaded - return ResultStatus::Success; + return LoadExec(); // Load the executable into memory for booting } ResultStatus AppLoader_NCCH::ReadCode(std::vector& buffer) const { @@ -257,7 +253,8 @@ ResultStatus AppLoader_NCCH::ReadRomFS(std::vector& buffer) const { buffer.resize(romfs_size); file->Seek(romfs_offset, SEEK_SET); - file->ReadBytes(&buffer[0], romfs_size); + if (file->ReadBytes(&buffer[0], romfs_size) != romfs_size) + return ResultStatus::Error; return ResultStatus::Success; } -- cgit v1.2.3