public async Task <Stream> OpenReadAsync(CancellationToken ct)
{
Stream stream = null;
System.Security.Cryptography.Aes aes = null;
ICryptoTransform decryptor = null;
try
{
stream = await _fileInfo.OpenReadAsync(ct);
var header = await AesHeader.ReadAsync(stream, ct);
aes = CreateAes(header.Version);
var key = FileSystem.ComputeKey(header.IV, header.Version);
decryptor = CreateTransform(aes, key, header.IV, AesMode.Decrypt); // disposed by CryptoStream
return(new CryptoStream(stream, decryptor, CryptoStreamMode.Read));
}
catch
{
decryptor?.Dispose();
stream?.Dispose();
throw;
}
finally
{
aes?.Dispose();
}
}
public static async Task <byte[]> GetContentBytesAsync(this IFileInfo fi, CancellationToken ct)
{
if (fi == null)
{
throw new ArgumentNullException(nameof(fi));
}
using var stream = await fi.OpenReadAsync(ct);
using var ms = new MemoryStream();
await stream.CopyToAsync(ms, 81920, ct);
return(ms.ToArray());
}
public static async Task <IFileInfo> CopyFileAsync(this IDirectoryInfo directory, IFileInfo file, string fileName, CancellationToken ct)
{
if (directory == null)
{
throw new ArgumentNullException(nameof(directory));
}
if (file == null)
{
throw new ArgumentNullException(nameof(file));
}
using var inputStream = await file.OpenReadAsync(ct).ConfigureAwait(false);
return(await directory.CreateFileAsync(fileName, inputStream, file.Length, ct).ConfigureAwait(false));
}
