public AesXtsFile(OpenMode mode, IFile baseFile, string path, ReadOnlySpan <byte> kekSeed, ReadOnlySpan <byte> verificationKey, int blockSize)
{
Mode = mode;
BaseFile = baseFile;
Path = path;
KekSeed = kekSeed.ToArray();
VerificationKey = verificationKey.ToArray();
BlockSize = blockSize;
Header = new AesXtsFileHeader(BaseFile);
if (!Header.TryDecryptHeader(Path, KekSeed, VerificationKey))
{
ThrowHelper.ThrowResult(ResultFs.AesXtsFileHeaderInvalidKeys, "NAX0 key derivation failed.");
}
if (HeaderLength + Util.AlignUp(Header.Size, 0x10) > baseFile.GetSize())
{
ThrowHelper.ThrowResult(ResultFs.AesXtsFileTooShort, "NAX0 key derivation failed.");
}
IStorage encStorage = BaseFile.AsStorage().Slice(HeaderLength, Util.AlignUp(Header.Size, 0x10));
BaseStorage = new CachedStorage(new Aes128XtsStorage(encStorage, Header.DecryptedKey1, Header.DecryptedKey2, BlockSize, true), 4, true);
}
private bool TryReadXtsHeader(string filePath, string keyPath, out AesXtsFileHeader header)
{
Debug.Assert(PathTools.IsNormalized(filePath.AsSpan()));
Debug.Assert(PathTools.IsNormalized(keyPath.AsSpan()));
using (IFile file = BaseFileSystem.OpenFile(filePath, OpenMode.Read))
{
header = new AesXtsFileHeader(file);
return(header.TryDecryptHeader(keyPath, KekSource, ValidationKey));
}
}
public AesXtsFile(OpenMode mode, IFile baseFile, string path, ReadOnlySpan <byte> kekSeed, ReadOnlySpan <byte> verificationKey, int blockSize)
{
Mode = mode;
BaseFile = baseFile;
Path = path;
KekSeed = kekSeed.ToArray();
VerificationKey = verificationKey.ToArray();
BlockSize = blockSize;
Header = new AesXtsFileHeader(BaseFile);
if (!Header.TryDecryptHeader(Path, KekSeed, VerificationKey))
{
throw new ArgumentException("NAX0 key derivation failed.");
}
IStorage encStorage = BaseFile.AsStorage().Slice(HeaderLength, Util.AlignUp(Header.Size, 0x10));
BaseStorage = new CachedStorage(new Aes128XtsStorage(encStorage, Header.DecryptedKey1, Header.DecryptedKey2, BlockSize, true), 4, true);
}
