/// <summary>
/// Add a new file id, and key/iv pair to the VolumeKey
/// </summary>
///
/// <param name="KeyStream">The stream containing the VolumeKey</param>
/// <param name="Key">The key</param>
/// <param name="Iv">The vector</param>
///
/// <returns>Returns true if the file id is known, otherwizse false</returns>
public static void Add(Stream KeyStream, byte[] Key, byte[] Iv)
{
using (MemoryStream keyMem = new MemoryStream())
{
// get the header
VolumeKey vkey = new VolumeKey(KeyStream);
int offset = ID_SEEK + (vkey.Count * ID_SIZE);
KeyStream.Seek(offset, SeekOrigin.Begin);
int kmlen = vkey.Count * (vkey.Description.KeySize + vkey.Description.IvSize);
// adjust the header params
vkey.Count++;
ArrayUtils.AddAt(ref vkey.FileId, vkey.FileId[vkey.FileId.Length - 1]++, vkey.Count);
ArrayUtils.AddAt(ref vkey.State, (byte)0, vkey.Count);
// copy header to mem
vkey.ToStream().WriteTo(keyMem);
byte[] data = new byte[kmlen];
// copy existing key/iv pairs
KeyStream.Read(data, 0, data.Length);
keyMem.Write(data, 0, data.Length);
// write new
keyMem.Write(Key, 0, Key.Length);
keyMem.Write(Iv, 0, Iv.Length);
// overwrite stream w/ new
KeyStream.Seek(0, SeekOrigin.Begin);
keyMem.WriteTo(KeyStream);
}
}