/// <summary>
/// Extract a KeyParams and CipherDescription from a VolumeKey stream
/// </summary>
///
/// <param name="KeyStream">The stream containing the VolumeKey</param>
/// <param name="Index">The index of the key set to extract</param>
/// <param name="Description">The <see cref="CipherDescription"/> that receives the cipher description</param>
/// <param name="KeyParam">The <see cref="KeyParams"/> container that receives the key material from the file</param>
///
/// <exception cref="CryptoProcessingException">Thrown if the key file could not be found</exception>
public void Extract(Stream KeyStream, int Index, out CipherDescription Description, out KeyParams KeyParam)
{
if (KeyStream == null || KeyStream.Length < 96)
{
throw new CryptoProcessingException("VolumeFactory:Extract", "The key file could not be loaded! Check the stream.", new FileNotFoundException());
}
VolumeKey vkey = new VolumeKey(KeyStream);
Description = vkey.Description;
KeyParam = VolumeKey.AtIndex(KeyStream, Index);
}
/// <summary>
/// Encrypt the files in the specified directory
/// </summary>
///
/// <param name="FilePaths">A list of the files to be processed</param>
///
/// <exception cref="CryptoProcessingException">Thrown if the VolumeKey does not contain enough keys to encrypt all the files in the directory</exception>
public void Encrypt(string[] FilePaths)
{
if (FilePaths.Length < 1)
{
throw new CryptoProcessingException("VolumeCipher:Transform", "The file paths list is empty!", new ArgumentException());
}
if (m_volumeKey.KeyCount() < FilePaths.Length)
{
throw new CryptoProcessingException("VolumeCipher:Transform", "Not enough keys in the volume key to encrypt this directory!", new ArgumentException());
}
InitializeProgress(FilePaths);
if (m_progressTotal < 1)
{
throw new CryptoProcessingException("VolumeCipher:Initialize", "The files are all zero bytes!", new ArgumentException());
}
long prgCtr = 0;
for (int i = 0; i < FilePaths.Length; ++i)
{
int index = m_volumeKey.NextSubKey();
KeyParams key = VolumeKey.AtIndex(m_keyStream, index);
if (key == null)
{
if (ErrorNotification != null)
{
ErrorNotification(this, string.Format("The file {0}; has no key assigned", FilePaths[i]));
}
}
else
{
FileStream inpStream = GetStream(FilePaths[i], true);
FileStream outStream = GetStream(FilePaths[i], false);
if (inpStream == null || outStream == null)
{
if (ErrorNotification != null)
{
ErrorNotification(this, string.Format("The file {0}; could not be written to", FilePaths[i]));
}
}
else
{
m_volumeKey.State[index] = (byte)VolumeKeyStates.Encrypted;
m_cipherStream.Initialize(true, key);
m_cipherStream.Write(inpStream, outStream);
// write the header
VolumeHeader vh = new VolumeHeader(m_volumeKey.Tag, m_volumeKey.FileId[index]);
outStream.Write(vh.ToBytes(), 0, VolumeHeader.GetHeaderSize);
prgCtr += inpStream.Position;
CalculateProgress(prgCtr);
inpStream.Dispose();
outStream.Dispose();
UpdateKey();
}
}
}
}