public string DecryptMessageWithKey(string privateKey, string messageData, string encryptedDecryptionKey,
string hashOfMessage, out string encryptionKey)
{
Debug.WriteLine("encryptedPassword for AES: " + encryptedDecryptionKey);
encryptionKey = DecryptWithKey(encryptedDecryptionKey, privateKey);
Debug.WriteLine("Decrypted password for AES: " + encryptionKey);
Contract.Assert(encryptionKey != string.Empty, "Encryption key is null");
// decrypt message
string decryptedMessage = new SymmetricCryptoProvider().DecryptWithKey(messageData, encryptionKey);
//verify hash:
Contract.Assert(SymmetricCryptoProvider.GetSecureHashForString(decryptedMessage) == hashOfMessage,
"Original hash does not equal decrypted hash!");
return(decryptedMessage);
}
// https://code.google.com/p/cryptico/
public string EncryptMessageWithKey(string message, string publicKey, out string encryptedPassword,
out string hashOfMessage)
{
// get a hash of the message
hashOfMessage = SymmetricCryptoProvider.GetSecureHashForString(message);
// generate a password:
string encryptionKeyForAES = SymmetricCryptoProvider.GenerateKeyPhrase();
Debug.WriteLine("encryptionKey for AES: " + encryptionKeyForAES);
// encrypt the message with AES using the encryption key
string encryptedMessage = new SymmetricCryptoProvider().EncryptWithKey(message, encryptionKeyForAES);
// encrypt the Key:
encryptedPassword = EncryptWithKey(encryptionKeyForAES, publicKey);
Debug.WriteLine("encryptedPassword for AES: " + encryptedPassword);
return(encryptedMessage);
}