public SecureString Decrypt(string cipherText)
{
if (string.IsNullOrEmpty(cipherText))
{
return(null);
}
var plainData = cipherText.Split('|');
if (plainData.Length < 3)
{
return(null);
}
var data = new InsecureAesData
{
CipherBytes = Convert.FromBase64String(plainData[0]),
Key = Convert.FromBase64String(plainData[1]),
IV = Convert.FromBase64String(plainData[2])
};
Decrypt(data);
var plain = Encoding.UTF8.GetString(data.PlainBytes);
unsafe
{
fixed(char *passwordChars = plain)
{
var securePassword = new SecureString(passwordChars, plain.Length);
securePassword.MakeReadOnly();
return(securePassword);
}
}
}
public string Encrypt(SecureString plainText)
{
if (plainText == null)
{
return(string.Empty);
}
var unsecure = ConvertToUnsecureString(plainText);
if (string.IsNullOrEmpty(unsecure))
{
return(string.Empty);
}
var data = new InsecureAesData {
PlainBytes = Encoding.UTF8.GetBytes(unsecure)
};
Encrypt(data);
// UNDONE:
// This isn't even secure! Maybe just a tad better than plain text
// How can I store public and IV in a secure way?
return(string.Format(
"{0}|{1}|{2}",
Convert.ToBase64String(data.CipherBytes),
Convert.ToBase64String(data.Key),
Convert.ToBase64String(data.IV)));
}
private void Encrypt(InsecureAesData data)
{
RijndaelManaged aes = null;
MemoryStream msEncrypt = null;
CryptoStream csEncrypt = null;
try
{
aes = new RijndaelManaged();
aes.GenerateKey();
aes.GenerateIV();
ICryptoTransform encryptor = aes.CreateEncryptor();
msEncrypt = new MemoryStream();
csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write);
csEncrypt.Write(data.PlainBytes, 0, data.PlainBytes.Length);
csEncrypt.Close();
csEncrypt = null;
data.CipherBytes = msEncrypt.ToArray();
data.Key = aes.Key;
data.IV = aes.IV;
}
// ReSharper disable once EmptyGeneralCatchClause
catch
{
// UNDONE : REPORT EXCEPTION
}
finally
{
if (csEncrypt != null)
{
csEncrypt.Close();
}
if (msEncrypt != null)
{
msEncrypt.Close();
}
// Clear the AesManaged object.
if (aes != null)
{
aes.Clear();
}
}
}
private void Decrypt(InsecureAesData data)
{
RijndaelManaged aes = null;
MemoryStream msDecrypt = null;
CryptoStream csDecrypt = null;
try
{
aes = new RijndaelManaged();
aes.Key = data.Key;
aes.IV = data.IV;
ICryptoTransform decryptor = aes.CreateDecryptor();
msDecrypt = new MemoryStream(data.CipherBytes);
csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read);
byte[] buffer = new byte[data.CipherBytes.Length];
int read = csDecrypt.Read(buffer, 0, buffer.Length);
data.PlainBytes = new byte[read];
Buffer.BlockCopy(buffer, 0, data.PlainBytes, 0, read);
}
// ReSharper disable once EmptyGeneralCatchClause
catch
{
// UNDONE : REPORT EXCEPTION
}
finally
{
if (csDecrypt != null)
{
csDecrypt.Close();
}
if (msDecrypt != null)
{
msDecrypt.Close();
}
// Clear the AesManaged object.
if (aes != null)
{
aes.Clear();
}
}
}
