private void btnDecrypt_Click(object sender, EventArgs e)
{
txtException.Text = null;
txtDecrypted.Text = null;
try
{
byte[] cipherText = QuickCrypto.StringToByteArray(txtEncryptedToken.Text.Substring(32));
byte[] ivBytes = QuickCrypto.StringToByteArray(txtEncryptedToken.Text.Substring(0, 32));
string plaintext = null;
using (Aes aesAlg = Aes.Create())
{
aesAlg.Key = encryptionKey;
aesAlg.IV = ivBytes;
aesAlg.Padding = PaddingMode.None;
ICryptoTransform decryptor = aesAlg.CreateDecryptor(aesAlg.Key, aesAlg.IV);
using (MemoryStream msDecrypt = new MemoryStream(cipherText))
using (CryptoStream csDecrypt = new CryptoStream(msDecrypt, decryptor, CryptoStreamMode.Read))
using (StreamReader srDecrypt = new StreamReader(csDecrypt))
{
plaintext = srDecrypt.ReadToEnd();
}
}
for (int i = 0; i < plaintext.Length; i++)
{
char c = plaintext[i];
if ((int)c < 32 || (int)c > 126)
{
txtDecrypted.Text += @"\" + (int)c;
}
else
{
txtDecrypted.Text += c;
}
}
}
catch (Exception ex)
{
txtException.Text = ex.ToString();
}
}
public TransactionResult Get(string ticket)
{
if (String.IsNullOrEmpty(ticket))
{
return(new TransactionResult());
}
var encryptionKeyString = "4f256766a4075027695bd48b444e1ac5c7c17385a1b4f1779e6385da24d97997";
byte[] encryptionKey = QuickCrypto.StringToByteArray(encryptionKeyString);
byte[] ticketBytes = QuickCrypto.StringToByteArray(ticket.Substring(32));
byte[] ivBytes = QuickCrypto.StringToByteArray(ticket.Substring(0, 32));
string decrypted;
try
{
decrypted = QuickCrypto.DecryptStringFromBytes_Aes(
ticketBytes, encryptionKey, ivBytes);
}
catch
{
return(new TransactionResult()
{
Status = "Bad Token"
});
}
long accountNumber = 0;
string[] ticketParts = decrypted.Split('|');
// some fake validation
bool validAccount = Int64.TryParse(ticketParts[0], out accountNumber);
if (ticketParts.Length == 4 && validAccount)
{
return(new TransactionResult()
{
Status = "OK", ConfirmationNumber = 123
});
}
return(new TransactionResult()
{
Status = "Invalid Request"
});
}
public Form1()
{
InitializeComponent();
encryptionKey = QuickCrypto.StringToByteArray(this.encryptionKeyString);
}