public Nax0(Keyset keyset, Stream stream, string sdPath, bool keepOpen)
{
stream.Position = 0;
KeepOpen = keepOpen;
ReadHeader(stream);
DeriveKeys(keyset, sdPath, stream);
stream.Position = 0x4000;
Xts xts = XtsAes128.Create(Keys[0], Keys[1]);
Stream = new RandomAccessSectorStream(new XtsSectorStream(stream, xts, 0x4000, 0x4000), keepOpen);
}
// Thanks, Falo!
public static byte[] AES_XTS(byte[] Key1, byte[] Key2, int SectorSize, byte[] Data, ulong Sector)
{
byte[] BlockData;
Xts XTS128 = XtsAes128.Create(Key1, Key2, true);
int Blocks;
var MemStrm = new MemoryStream();
var Writer = new BinaryWriter(MemStrm);
var CryptoTransform = XTS128.CreateEncryptor();
BlockData = new byte[SectorSize];
Blocks = Data.Length / SectorSize;
for (int i = 0; i < Blocks; i++)
{
CryptoTransform.TransformBlock(Data, i * SectorSize, SectorSize, BlockData, 0, Sector++);
Writer.Write(BlockData);
}
return(MemStrm.ToArray());
}
public static byte[] DecryptNCAHeader(string selectedFile, long offset)
{
byte[] array = new byte[3072];
if (File.Exists(selectedFile))
{
FileStream fileStream = new FileStream(selectedFile, FileMode.Open, FileAccess.Read);
fileStream.Position = offset;
fileStream.Read(array, 0, 3072);
File.WriteAllBytes(selectedFile + ".tmp", array);
Xts xts = XtsAes128.Create(Form1.NcaHeaderEncryptionKey1_Prod, Form1.NcaHeaderEncryptionKey2_Prod);
using (BinaryReader binaryReader = new BinaryReader(File.OpenRead(selectedFile + ".tmp"))) {
using (XtsStream xtsStream = new XtsStream(binaryReader.BaseStream, xts, 512)) {
xtsStream.Read(array, 0, 3072);
}
}
File.Delete(selectedFile + ".tmp");
fileStream.Close();
}
return(array);
}
/* Switched to MemoryStream and simplified code
* No idea if anything broke
*/
public static byte[] DecryptNCAHeader(string selectedFile, long offset)
{
byte[] array = new byte[3072];
if (File.Exists(selectedFile))
{
using (var stream = new MemoryStream()) {
FileStream fs = new FileStream(selectedFile, FileMode.Open, FileAccess.Read);
fs.Position = offset;
fs.Read(array, 0, 3072);
fs.Close();
stream.Write(array, 0, array.Length);
stream.Position = 0;
Xts xts = XtsAes128.Create(Form1.NcaHeaderEncryptionKey1_Prod, Form1.NcaHeaderEncryptionKey2_Prod);
using (XtsStream xtsStream = new XtsStream(stream, xts, 512)) {
xtsStream.Read(array, 0, 3072);
}
}
}
return(array);
}
public void SetXts(Xts xts)
{
Xts = xts;
}
protected override async Task InitMetadataImplAsync(CancellationToken cancel = default)
{
Memory <byte> firstSectorData = new byte[XtsAesMetaDataSize];
// ヘッダの読み込みを試行する
int readSize = await this.PhysicalReadAsync(0, firstSectorData, cancel);
if (readSize == XtsAesMetaDataSize)
{
var metaDataParseResult = TryParseMetaData(firstSectorData);
metaDataParseResult.ThrowIfException();
var metaData = metaDataParseResult.Value !;
// パスワード検査
if (Secure.VeritySaltedPassword(metaData.SaltedPassword, this.CurrentPassword) == false)
{
throw new CoresException("XtsAesRandomAccess: Incorrect password.");
}
// 秘密鍵解読
var decrypted = ChaChaPoly.EasyDecryptWithPassword(metaData.MasterKeyEncryptedByPassword._GetHexBytes(), this.CurrentPassword);
decrypted.ThrowIfException();
// 秘密鍵サイズ検査
if (decrypted.Value.Length != XtsAesKeySize)
{
throw new CoresException("XtsAesRandomAccess: decrypted.Value.Length != XtsAesKeySize");
}
this.CurrentMasterKey = decrypted.Value;
this.CurrentMetaData = metaData;
}
else if (readSize == 0)
{
// ファイルの内容が存在しない
// マスターキーを新規作成する
this.CurrentMasterKey = Secure.Rand(XtsAesKeySize);
// メタデータを新規作成する
var metaData = new XtsAesRandomAccessMetaData
{
Version = 1,
VirtualSize = 0,
SaltedPassword = Secure.SaltPassword(this.CurrentPassword),
MasterKeyEncryptedByPassword = ChaChaPoly.EasyEncryptWithPassword(this.CurrentMasterKey, this.CurrentPassword)._GetHexString(),
};
this.CurrentMetaData = metaData;
// メタデータを書き込みする
await WriteMetaDataAsync(cancel);
}
else
{
// 不正 ここには来ないはず
throw new CoresException($"XtsAesRandomAccess: Invalid readSize: {readSize}");
}
// XTS を作成
this.CurrentXts = XtsAes256.Create(this.CurrentMasterKey.ToArray());
this.CurrentEncrypter = this.CurrentXts.CreateEncryptor();
this.CurrentDescrypter = this.CurrentXts.CreateDecryptor();
}
public VideoCacheDownloadOperationOutputWithEncryption(StorageFile destinationFile, XTSSharp.Xts xts)
{
_destinationFile = destinationFile;
_xts = xts;
}
