Mirrors/yuzu
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

crypto: Eliminate magic constants

Browse source
This commit is contained in:
Zach Hilman 2018-08-18 21:14:57 -04:00
parent 61a5b56abd
commit 42dc856ce1
4 changed files with 38 additions and 32 deletions
Download patch file Download diff file Expand all files Collapse all files

2
src/core/crypto/key_manager.cpp
View file

@ -102,7 +102,7 @@ Loader::ResultStatus DeriveSDKeys(std::array<Key256, 2>& sd_keys, const KeyManag
AESCipher<Key128> cipher(sd_kek, Mode::ECB);
for (size_t i = 0; i < 2; ++i) {
for (size_t j = 0; j < 0x20; ++j)
for (size_t j = 0; j < sd_key_sources[i].size(); ++j)
sd_key_sources[i][j] ^= sd_seed[j & 0xF];
cipher.Transcode(sd_key_sources[i].data(), sd_key_sources[i].size(), sd_keys[i].data(),
Op::Decrypt);

33
src/core/crypto/xts_encryption_layer.cpp
View file

@ -8,6 +8,8 @@
namespace Core::Crypto {
constexpr u64 XTS_SECTOR_SIZE = 0x4000;
XTSEncryptionLayer::XTSEncryptionLayer(FileSys::VirtualFile base_, Key256 key_)
: EncryptionLayer(std::move(base_)), cipher(key_, Mode::XTS) {}
@ -17,34 +19,35 @@ size_t XTSEncryptionLayer::Read(u8* data, size_t length, size_t offset) const {
const auto sector_offset = offset & 0x3FFF;
if (sector_offset == 0) {
if (length % 0x4000 == 0) {
if (length % XTS_SECTOR_SIZE == 0) {
std::vector<u8> raw = base->ReadBytes(length, offset);
cipher.XTSTranscode(raw.data(), raw.size(), data, offset / 0x4000, 0x4000, Op::Decrypt);
cipher.XTSTranscode(raw.data(), raw.size(), data, offset / XTS_SECTOR_SIZE,
XTS_SECTOR_SIZE, Op::Decrypt);
return raw.size();
}
if (length > 0x4000) {
const auto rem = length % 0x4000;
if (length > XTS_SECTOR_SIZE) {
const auto rem = length % XTS_SECTOR_SIZE;
const auto read = length - rem;
return Read(data, read, offset) + Read(data + read, rem, offset + read);
}
std::vector<u8> buffer = base->ReadBytes(0x4000, offset);
if (buffer.size() < 0x4000)
buffer.resize(0x4000);
cipher.XTSTranscode(buffer.data(), buffer.size(), buffer.data(), offset / 0x4000, 0x4000,
Op::Decrypt);
std::vector<u8> buffer = base->ReadBytes(XTS_SECTOR_SIZE, offset);
if (buffer.size() < XTS_SECTOR_SIZE)
buffer.resize(XTS_SECTOR_SIZE);
cipher.XTSTranscode(buffer.data(), buffer.size(), buffer.data(), offset / XTS_SECTOR_SIZE,
XTS_SECTOR_SIZE, Op::Decrypt);
std::memcpy(data, buffer.data(), std::min(buffer.size(), length));
return std::min(buffer.size(), length);
}
// offset does not fall on block boundary (0x4000)
std::vector<u8> block = base->ReadBytes(0x4000, offset - sector_offset);
if (block.size() < 0x4000)
block.resize(0x4000);
cipher.XTSTranscode(block.data(), block.size(), block.data(), (offset - sector_offset) / 0x4000,
0x4000, Op::Decrypt);
const size_t read = 0x4000 - sector_offset;
if (block.size() < XTS_SECTOR_SIZE)
block.resize(XTS_SECTOR_SIZE);
cipher.XTSTranscode(block.data(), block.size(), block.data(),
(offset - sector_offset) / XTS_SECTOR_SIZE, XTS_SECTOR_SIZE, Op::Decrypt);
const size_t read = XTS_SECTOR_SIZE - sector_offset;
if (length + sector_offset < 0x4000) {
if (length + sector_offset < XTS_SECTOR_SIZE) {
std::memcpy(data, block.data() + sector_offset, std::min<u64>(length, read));
return std::min<u64>(length, read);
}