internal bool OpenStream()
{
if (Mode == StreamMode.GetHeader || Mode == StreamMode.PushHeader)
{
parent.ExceptionHandler.CloseConnection("InvalidOperation",
$"You should not try to open a file stream with {Mode}",
nameof(FTEventArgs), nameof(OpenStream));
return(false);
}
FileStream fileStream;
FileMode fileMode;
FileAccess fileAccess;
FileShare fileShare;
System.Security.Cryptography.CryptoStreamMode streamMode;
CryptographicOperation operation;
if (Mode == StreamMode.GetFile)
{
fileMode = FileMode.Create;
fileAccess = FileAccess.Write;
fileShare = FileShare.None;
streamMode = System.Security.Cryptography.CryptoStreamMode.Write;
operation = CryptographicOperation.Decrypt;
}
else // Mode == StreamMode.PushFile
{
fileMode = FileMode.Open;
fileAccess = FileAccess.Read;
fileShare = FileShare.Read;
streamMode = System.Security.Cryptography.CryptoStreamMode.Read;
operation = CryptographicOperation.Encrypt;
}
try
{
fileStream = new FileStream(Path, fileMode, fileAccess, fileShare);
}
catch (Exception ex)
{
parent.ExceptionHandler.CloseConnection(ex);
return(false);
}
if (FileMeta.FileEncryption == ContentAlgorithm.None || !FileMeta.Available)
{
Stream = new ShaStream(fileStream, streamMode);
}
else if (FileMeta.FileEncryption == ContentAlgorithm.Aes256Cbc)
{
Stream = new AesShaStream(fileStream, FileMeta.FileKey, streamMode, operation);
}
else
{
parent.ExceptionHandler.CloseConnection("InvalidFileAlgorithm",
"Cannot run file transfer with " + FileMeta.FileEncryption,
nameof(FTEventArgs), nameof(OpenStream));
return(false);
}
return(true);
}
public void TestDecryptWriteModeFail(string input)
{
byte[] ciphertext = Util.GetBytes(input);
byte[] key = Util.GetBytes("fe627bd19db579ddd5e4ce42046f45b2fb708d98a6c6230c315df2760d4966ea");
MemoryStream baseStream = new MemoryStream();
AesShaStream stream = new AesShaStream(baseStream, key, CryptoStreamMode.Write, CryptographicOperation.Decrypt);
stream.Write(ciphertext, 0, ciphertext.Length);
Assert.ThrowsException <CryptographicException>(() => stream.FlushFinalBlock());
Assert.ThrowsException <CryptographicException>(() => stream.Dispose());
Assert.IsFalse(baseStream.CanRead);
Assert.IsFalse(baseStream.CanWrite);
}
