diff --git a/Source/Core/Core/HW/GCMemcard/GCMemcard.cpp b/Source/Core/Core/HW/GCMemcard/GCMemcard.cpp index c0dccde285..6751669783 100644 --- a/Source/Core/Core/HW/GCMemcard/GCMemcard.cpp +++ b/Source/Core/Core/HW/GCMemcard/GCMemcard.cpp @@ -5,6 +5,7 @@ #include "Core/HW/GCMemcard/GCMemcard.h" #include +#include #include #include #include @@ -270,54 +271,50 @@ bool GCMemcard::Save() return mcdFile.Close(); } -void calc_checksumsBE(const u16* buf, u32 length, u16* csum, u16* inv_csum) +std::pair CalculateMemcardChecksums(const u8* data, size_t size) { - *csum = *inv_csum = 0; + assert(size % 2 == 0); + u16 csum = 0; + u16 inv_csum = 0; - for (u32 i = 0; i < length; ++i) + for (size_t i = 0; i < size; i += 2) { - // weird warnings here - *csum += BE16(buf[i]); - *inv_csum += BE16((u16)(buf[i] ^ 0xffff)); - } - *csum = BE16(*csum); - *inv_csum = BE16(*inv_csum); - if (*csum == 0xffff) - { - *csum = 0; - } - if (*inv_csum == 0xffff) - { - *inv_csum = 0; + u16 d = Common::swap16(&data[i]); + csum += d; + inv_csum += static_cast(d ^ 0xffff); } + + csum = Common::swap16(csum); + inv_csum = Common::swap16(inv_csum); + + if (csum == 0xffff) + csum = 0; + if (inv_csum == 0xffff) + inv_csum = 0; + + return std::make_pair(csum, inv_csum); } u32 GCMemcard::TestChecksums() const { - u16 csum = 0, csum_inv = 0; + const auto [csum_hdr, cinv_hdr] = m_header_block.CalculateChecksums(); + const auto [csum_dir0, cinv_dir0] = m_directory_blocks[0].CalculateChecksums(); + const auto [csum_dir1, cinv_dir1] = m_directory_blocks[1].CalculateChecksums(); + const auto [csum_bat0, cinv_bat0] = m_bat_blocks[0].CalculateChecksums(); + const auto [csum_bat1, cinv_bat1] = m_bat_blocks[1].CalculateChecksums(); u32 results = 0; - - calc_checksumsBE((u16*)&m_header_block, 0xFE, &csum, &csum_inv); - if ((m_header_block.m_checksum != csum) || (m_header_block.m_checksum_inv != csum_inv)) + if ((m_header_block.m_checksum != csum_hdr) || (m_header_block.m_checksum_inv != cinv_hdr)) results |= 1; - - calc_checksumsBE((u16*)&m_directory_blocks[0], 0xFFE, &csum, &csum_inv); - if ((m_directory_blocks[0].m_checksum != csum) || - (m_directory_blocks[0].m_checksum_inv != csum_inv)) + if ((m_directory_blocks[0].m_checksum != csum_dir0) || + (m_directory_blocks[0].m_checksum_inv != cinv_dir0)) results |= 2; - - calc_checksumsBE((u16*)&m_directory_blocks[1], 0xFFE, &csum, &csum_inv); - if ((m_directory_blocks[1].m_checksum != csum) || - (m_directory_blocks[1].m_checksum_inv != csum_inv)) + if ((m_directory_blocks[1].m_checksum != csum_dir1) || + (m_directory_blocks[1].m_checksum_inv != cinv_dir1)) results |= 4; - - calc_checksumsBE((u16*)(((u8*)&m_bat_blocks[0]) + 4), 0xFFE, &csum, &csum_inv); - if ((m_bat_blocks[0].m_checksum != csum) || (m_bat_blocks[0].m_checksum_inv != csum_inv)) + if ((m_bat_blocks[0].m_checksum != csum_bat0) || (m_bat_blocks[0].m_checksum_inv != cinv_bat0)) results |= 8; - - calc_checksumsBE((u16*)(((u8*)&m_bat_blocks[1]) + 4), 0xFFE, &csum, &csum_inv); - if ((m_bat_blocks[1].m_checksum != csum) || (m_bat_blocks[1].m_checksum_inv != csum_inv)) + if ((m_bat_blocks[1].m_checksum != csum_bat1) || (m_bat_blocks[1].m_checksum_inv != cinv_bat1)) results |= 16; return results; @@ -328,16 +325,11 @@ bool GCMemcard::FixChecksums() if (!m_valid) return false; - calc_checksumsBE((u16*)&m_header_block, 0xFE, &m_header_block.m_checksum, - &m_header_block.m_checksum_inv); - calc_checksumsBE((u16*)&m_directory_blocks[0], 0xFFE, &m_directory_blocks[0].m_checksum, - &m_directory_blocks[0].m_checksum_inv); - calc_checksumsBE((u16*)&m_directory_blocks[1], 0xFFE, &m_directory_blocks[1].m_checksum, - &m_directory_blocks[1].m_checksum_inv); - calc_checksumsBE((u16*)&m_bat_blocks[0] + 2, 0xFFE, &m_bat_blocks[0].m_checksum, - &m_bat_blocks[0].m_checksum_inv); - calc_checksumsBE((u16*)&m_bat_blocks[1] + 2, 0xFFE, &m_bat_blocks[1].m_checksum, - &m_bat_blocks[1].m_checksum_inv); + m_header_block.FixChecksums(); + m_directory_blocks[0].FixChecksums(); + m_directory_blocks[1].FixChecksums(); + m_bat_blocks[0].FixChecksums(); + m_bat_blocks[1].FixChecksums(); return true; } @@ -656,7 +648,7 @@ bool BlockAlloc::ClearBlocks(u16 starting_block, u16 block_count) void BlockAlloc::FixChecksums() { - calc_checksumsBE((u16*)&m_update_counter, 0xFFE, &m_checksum, &m_checksum_inv); + std::tie(m_checksum, m_checksum_inv) = CalculateChecksums(); } u16 BlockAlloc::AssignBlocksContiguous(u16 length) @@ -677,6 +669,19 @@ u16 BlockAlloc::AssignBlocksContiguous(u16 length) return starting; } +std::pair BlockAlloc::CalculateChecksums() const +{ + static_assert(std::is_trivially_copyable()); + + std::array raw; + memcpy(raw.data(), this, raw.size()); + + constexpr size_t checksum_area_start = offsetof(BlockAlloc, m_update_counter); + constexpr size_t checksum_area_end = sizeof(BlockAlloc); + constexpr size_t checksum_area_size = checksum_area_end - checksum_area_start; + return CalculateMemcardChecksums(&raw[checksum_area_start], checksum_area_size); +} + u32 GCMemcard::GetSaveData(u8 index, std::vector& Blocks) const { if (!m_valid) @@ -1452,7 +1457,7 @@ Header::Header(int slot, u16 size_mbits, bool shift_jis) memset(m_unknown_2.data(), 0, m_unknown_2.size()); // = _viReg[55]; static vu16* const _viReg = (u16*)0xCC002000; m_device_id = 0; - calc_checksumsBE((u16*)this, 0xFE, &m_checksum, &m_checksum_inv); + FixChecksums(); } std::pair Header::CalculateSerial() const @@ -1487,6 +1492,24 @@ std::string DEntry::GCI_FileName() const return Common::EscapeFileName(filename); } +void Header::FixChecksums() +{ + std::tie(m_checksum, m_checksum_inv) = CalculateChecksums(); +} + +std::pair Header::CalculateChecksums() const +{ + static_assert(std::is_trivially_copyable
()); + + std::array raw; + memcpy(raw.data(), this, raw.size()); + + constexpr size_t checksum_area_start = offsetof(Header, m_serial); + constexpr size_t checksum_area_end = offsetof(Header, m_checksum); + constexpr size_t checksum_area_size = checksum_area_end - checksum_area_start; + return CalculateMemcardChecksums(&raw[checksum_area_start], checksum_area_size); +} + Directory::Directory() { memset(this, 0xFF, BLOCK_SIZE); @@ -1507,5 +1530,18 @@ bool Directory::Replace(const DEntry& entry, size_t index) void Directory::FixChecksums() { - calc_checksumsBE((u16*)this, 0xFFE, &m_checksum, &m_checksum_inv); + std::tie(m_checksum, m_checksum_inv) = CalculateChecksums(); +} + +std::pair Directory::CalculateChecksums() const +{ + static_assert(std::is_trivially_copyable()); + + std::array raw; + memcpy(raw.data(), this, raw.size()); + + constexpr size_t checksum_area_start = offsetof(Directory, m_dir_entries); + constexpr size_t checksum_area_end = offsetof(Directory, m_checksum); + constexpr size_t checksum_area_size = checksum_area_end - checksum_area_start; + return CalculateMemcardChecksums(&raw[checksum_area_start], checksum_area_size); } diff --git a/Source/Core/Core/HW/GCMemcard/GCMemcard.h b/Source/Core/Core/HW/GCMemcard/GCMemcard.h index 7dc6ff2eec..3bcd579476 100644 --- a/Source/Core/Core/HW/GCMemcard/GCMemcard.h +++ b/Source/Core/Core/HW/GCMemcard/GCMemcard.h @@ -97,8 +97,6 @@ struct GCMBlock std::array m_block; }; -void calc_checksumsBE(const u16* buf, u32 length, u16* csum, u16* inv_csum); - #pragma pack(push, 1) struct Header { @@ -149,6 +147,9 @@ struct Header // Calculates the card serial numbers used for encrypting some save files. std::pair CalculateSerial() const; + + void FixChecksums(); + std::pair CalculateChecksums() const; }; static_assert(sizeof(Header) == BLOCK_SIZE); @@ -257,6 +258,7 @@ struct Directory bool Replace(const DEntry& entry, size_t index); void FixChecksums(); + std::pair CalculateChecksums() const; }; static_assert(sizeof(Directory) == BLOCK_SIZE); @@ -285,8 +287,10 @@ struct BlockAlloc u16 GetNextBlock(u16 block) const; u16 NextFreeBlock(u16 max_block, u16 starting_block = MC_FST_BLOCKS) const; bool ClearBlocks(u16 starting_block, u16 block_count); - void FixChecksums(); u16 AssignBlocksContiguous(u16 length); + + void FixChecksums(); + std::pair CalculateChecksums() const; }; static_assert(sizeof(BlockAlloc) == BLOCK_SIZE); #pragma pack(pop)