static public KIVPair LoadKeyIV()
{
if (!File.Exists(CONFIG_FILE_NAME))
{
return(null);
}
using (FileStream fs = new FileStream(CONFIG_FILE_NAME, FileMode.Open))
{
BinaryFormatter formatter = new BinaryFormatter();
try
{
KIVPair myKIV = (KIVPair)formatter.Deserialize(fs);
return(myKIV);
}
catch (Exception e)
{
WriteLog("Falha no Load do kiv, motivo: " + e.Message);
return(null);
}
finally
{
fs.Close();
}
}
}
public static void DefineKIV()
{
try
{
using (AesCryptoServiceProvider myAes = new AesCryptoServiceProvider())
{
// Encrypt the string to an array of bytes.
KIVPair kiv = new KIVPair(myAes.Key, myAes.IV);
WriteConfig(kiv);
}
}
catch (Exception e)
{
WriteLog(e.Message);
WriteLog(e.StackTrace);
}
}
public static void WriteConfig(KIVPair kiv)
{
try
{
// Construct a BinaryFormatter and use it to serialize the data to the stream.
FileStream fs = null;
BinaryFormatter formatter = new BinaryFormatter();
using (fs = new FileStream(CONFIG_FILE_NAME, FileMode.Create))
{
formatter.Serialize(fs, kiv);
}
}
catch (Exception e)
{
WriteLog("Falha ao salvar configurações, motivo: " + e.Message + "\n" + e.StackTrace);
}
}
public static byte[] EncryptStringToBytes_Aes(string plainText)
{
// Check arguments.
if (plainText == null || plainText.Length <= 0)
{
throw new ArgumentNullException("plainText");
}
byte[] encrypted;
try
{
// Create an AesManaged object
// with the specified key and IV.
using (AesManaged aesAlg = new AesManaged())
{
KIVPair kiv = LoadKeyIV();
// Create an encryptor to perform the stream transform.
ICryptoTransform encryptor = aesAlg.CreateEncryptor(kiv.K, kiv.IV);
// Create the streams used for encryption.
using (MemoryStream msEncrypt = new MemoryStream())
{
using (CryptoStream csEncrypt = new CryptoStream(msEncrypt, encryptor, CryptoStreamMode.Write))
{
using (StreamWriter swEncrypt = new StreamWriter(csEncrypt))
{
//Write all data to the stream.
swEncrypt.Write(plainText);
}
encrypted = msEncrypt.ToArray();
}
}
return(encrypted);
}
}
catch (Exception)
{
throw;
}
}
public static string DecryptStringFromBytes_Aes(byte[] cipherText)
{
// Check arguments.
if (cipherText == null || cipherText.Length <= 0)
{
throw new ArgumentNullException("cipherText");
}
// Declare the string used to hold
// the decrypted text.
string plaintext = null;
// Create an AesManaged object
// with the specified key and IV.
using (AesManaged aesAlg = new AesManaged())
{
KIVPair kiv = LoadKeyIV();
// Create a decryptor to perform the stream transform.
ICryptoTransform decryptor = aesAlg.CreateDecryptor(kiv.K, kiv.IV);
// Create the streams used for decryption.
using (MemoryStream msDecrypt = new MemoryStream(cipherText))
{
using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
{
using (StreamReader srDecrypt = new StreamReader(csDecrypt))
{
// Read the decrypted bytes from the decrypting stream
// and place them in a string.
plaintext = srDecrypt.ReadToEnd();
}
}
}
}
return(plaintext);
}
