/// <summary>
/// Opens users encrypted file. File is first decrypted and stored as a temporary file in a <em>temporary folder</em> after which is opened in a default app for that file set on the computer.
/// </summary>
/// <param name="pathOnEfs">The name of the encrypted file including files path and encrypted name with .at extension.</param>
/// <param name="ownerPublicKey">Public RSA key from the file owner used to check files signature.</param>
public void OpenFile(string pathOnEfs, RSAParameters ownerPublicKey)
{
var encryptedFile = new EncryptedFile(pathOnEfs.Substring(pathOnEfs.LastIndexOf('\\') + 1).Split('.')[0]);
var originalFile = encryptedFile.Decrypt(File.ReadAllBytes(pathOnEfs), currentUser.Id, currentUser.PrivateKey, ownerPublicKey);
var tempFilePath = Path.GetTempPath() + "Enigma-" + Guid.NewGuid().ToString() + "." + originalFile.FileExtension;
if (CanItBeStored(originalFile.FileContent.Length, tempFilePath.Substring(0, 2)))
{
// create a temporary file
CreateFile(originalFile.FileContent, tempFilePath);
// override existing encrypted file
var encryptedFileUpdated = encryptedFile.Flush();
if (CanItBeStored(encryptedFileUpdated.Length, pathOnEfs.Substring(0, 2)))
{
CreateFile(encryptedFileUpdated, pathOnEfs);
}
var startInfo = new ProcessStartInfo(tempFilePath);
Process.Start(startInfo);
}
else
{
throw new Exception("Insufficient storage available. File can't be read.");
}
}
/// <summary>
/// Downloads selected encrypted file. File is first decrypted after which is stored on the specified path on file system.
/// </summary>
/// <param name="pathOnEfs">The name of the file to downloaded.</param>
/// <param name="pathOnFs">Path on the file system where the file will be stored.</param>
/// <param name="ownerPublicKey">Public RSA key from the file owner used to check files signature.</param>
public void Download(string pathOnEfs, string pathOnFs, RSAParameters ownerPublicKey)
{
var encryptedFile = new EncryptedFile(pathOnEfs.Substring(pathOnEfs.LastIndexOf('\\') + 1).Split('.')[0]);
var originalFile = encryptedFile.Decrypt(File.ReadAllBytes(pathOnEfs), currentUser.Id, currentUser.PrivateKey, ownerPublicKey);
if (CanItBeStored(originalFile.FileContent.Length, pathOnFs.Substring(0, 2)))
{
// write a new unencrypted file
CreateFile(originalFile.FileContent, pathOnFs /* + "\\" + originalFile.GetOriginalFileFullName()*/);
// override existing encrypted file
CreateFile(encryptedFile.Flush(), pathOnEfs);
}
else
{
throw new Exception("Insufficient storage available. File can't be downloaded.");
}
}