/// <summary>
/// Encrypt string with aes-256. Retrun base 64 string with salt(chars 88).
/// </summary>
/// <param name="plainText">The plain text string.</param>
/// <param name="passPhrase">The password for the encryption.</param>
/// <returns></returns>
public static string Encrypt(string plainText, string passPhrase)
{
//get nedded form of passphrase and plaintest
byte[] key = Utils.SafeUTF8.GetBytes(passPhrase);
ArraySegment <byte> plain = new ArraySegment <byte>(Utils.SafeUTF8.GetBytes(plainText));
//generate random salt
CryptoRandom rng = new CryptoRandom();
byte[] rand = rng.NextBytes(64);
ArraySegment <byte> salt = new ArraySegment <byte>(rand);
string ssalt = Convert.ToBase64String(rand);
byte[] output = null;
output = EtM_CTR.Encrypt(key, plain, salt, rounds);
if (output == null)
{
return(null);
}
string sout = Convert.ToBase64String(output);
return(sout + ssalt);
}
/// <summary>
/// Decrypt base64 string with salt (chars 88)
/// </summary>
/// <param name="cipherText">cypher text with salt at the end.</param>
/// <param name="passPhrase">password for the decryption.</param>
/// <returns></returns>
public static string Decrypt(string cipherText, string passPhrase)
{
//get nedded form of passphrase and cyphertext
byte[] key = Utils.SafeUTF8.GetBytes(passPhrase);
string salt = cipherText.Substring(cipherText.Length - 88);
cipherText = cipherText.Substring(0, cipherText.Length - 88);
ArraySegment <byte> bytecyphertext = new ArraySegment <byte>(Convert.FromBase64String(cipherText));
ArraySegment <byte> bytesalt = new ArraySegment <byte>(Convert.FromBase64String(salt));
byte[] decout = EtM_CTR.Decrypt(key, bytecyphertext, bytesalt, rounds);
if (decout == null)
{
return(null);
}
return(Utils.SafeUTF8.GetString(decout));
}
