/// <summary>
/// Updates selected encrypted file with a specified unencrypted file.
/// </summary>
/// <param name="pathOnEfs">The name of the file to update.</param>
/// <param name="updateFile">Updated, unencrypted file.</param>
public void Update(string pathOnEfs, OriginalFile updateFile)
{
CertificateCheck("You cannot update files.");
if (updateFile.FileSize > 2_000_000_000)
{
throw new Exception("File can't be larger than 2 GB.");
}
if (!CanItBeStored(updateFile.FileSize))
{
throw new Exception("Insufficient storage available. File can't be uploaded.");
}
var encryptedFile = new EncryptedFile(pathOnEfs.Substring(pathOnEfs.LastIndexOf('\\') + 1).Split('.')[0]);
var updatedEncryptedFileRaw = encryptedFile.Update(updateFile, File.ReadAllBytes(pathOnEfs), currentUser.Id, currentUser.PrivateKey);
// Name update is always necessary because file's IV has been changed and possibly a new file has a different name.
encryptedFile.NameEncryption(updateFile.GetOriginalFileFullName(),
new AesAlgorithm(((SecurityDescriptor)encryptedFile.Headers[1]).GetKey((int)currentUser.Id, currentUser.PrivateKey),
((SecurityDescriptor)encryptedFile.Headers[1]).IV, "OFB"));
// delete the old encrypted file
DeleteFile(pathOnEfs);
if (CanItBeStored(updatedEncryptedFileRaw.Length))
{
CreateFile(updatedEncryptedFileRaw, pathOnEfs.Substring(0, pathOnEfs.LastIndexOf('\\')) + "\\" + encryptedFile.GetEncryptedFileFullName());
}
else
{
throw new Exception("Insufficient storage available. File can't be updated.");
}
}
