using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Threading.Tasks; using System.Windows.Forms; using System.Security.Cryptography; namespace WindowsFormsApp1 { public partial class Form1 : Form { public string publicKeyString; public string privateKeyString; public string klucz_prywatny; public string encryptedText; public string szyfr; public string klucz_publiczny; public Form1() { InitializeComponent(); } private void btnPublic_key_Click(object sender, EventArgs e) { var cryptoServiceProvider = new RSACryptoServiceProvider(2048); //2048 - Długość klucza var publicKey = cryptoServiceProvider.ExportParameters(false); //Generowanie klucza publiczny publicKeyString = GetKeyString(publicKey); tbPublic_Key.Text = publicKeyString; klucz_publiczny = publicKeyString; } private void btnPrivate_key_Click(object sender, EventArgs e) { var cryptoServiceProvider = new RSACryptoServiceProvider(2048); //2048 - Długość klucza var privateKey = cryptoServiceProvider.ExportParameters(true); //Generowanie klucza prywatnego privateKeyString = GetKeyString(privateKey); lblPrivate_Key.Text = privateKeyString; klucz_prywatny = privateKeyString; } public static string GetKeyString(RSAParameters publicKey) { var stringWriter = new System.IO.StringWriter(); var xmlSerializer = new System.Xml.Serialization.XmlSerializer(typeof(RSAParameters)); xmlSerializer.Serialize(stringWriter, publicKey); return stringWriter.ToString(); } private void btnEncryptiontext_Click(object sender, EventArgs e) { string tekst = textBox_text.Text; encryptedText = Encrypt(tekst, publicKeyString); //Szyfrowanie za pomocą klucza publicznego lbl_Encryptiontxt.Text = encryptedText; szyfr = encryptedText; if (publicKeyString == null) { MessageBox.Show("Najpierw wygeneruj kklucz", "Error"); } } public static string Encrypt(string tekst, string publicKeyString) { var bytesToEncrypt = Encoding.UTF8.GetBytes(tekst); using (var rsa = new RSACryptoServiceProvider(2048)) { try { if (publicKeyString == null) { MessageBox.Show("Najpierw wygeneruj kklucz", "Error"); } else { rsa.FromXmlString(publicKeyString.ToString()); } var encryptedData = rsa.Encrypt(bytesToEncrypt, true); var base64Encrypted = Convert.ToBase64String(encryptedData); return base64Encrypted; } finally { rsa.PersistKeyInCsp = false; } } } private void btn_Decrypttxt_Click(object sender, EventArgs e) { string decryptedText = Decrypt(szyfr, klucz_prywatny); lbl_Decryptiontxt.Text = decryptedText; } public static string Decrypt(string szyfr, string klucz_prywatny) { var bytesToDescrypt = Encoding.UTF8.GetBytes(szyfr); using (var rsa = new RSACryptoServiceProvider(2048)) { try { // server decrypting data with private key rsa.FromXmlString(klucz_prywatny); var resultBytes = Convert.FromBase64String(szyfr); var decryptedBytes = rsa.Decrypt(resultBytes, true); var decryptedData = Encoding.UTF8.GetString(decryptedBytes); return decryptedData.ToString(); } finally { rsa.PersistKeyInCsp = false; } } } private void Form1_Load(object sender, EventArgs e) { } } }