C++ Crypto++ RSA Encryption?

Question

Qt

#include <cryptopp/modes.h>
#include <cryptopp/osrng.h>
#include <cryptopp/rsa.h>
#include <cryptopp/sha.h>

class MyClass
{

    CryptoPP::AutoSeededRandomPool rng;
    CryptoPP::RSA::PrivateKey privateKey;
    CryptoPP::RSA::PublicKey publicKey;
public:
                MyClass()
                {
  CryptoPP::RSAES_OAEP_SHA_Decryptor priv( rng, 4096 );
  CryptoPP::RSAES_OAEP_SHA_Decryptor pri( rng, 2048 );
  CryptoPP::InvertibleRSAFunction params;
  params.GenerateRandomWithKeySize( rng, 1536 );
  privateKey = CryptoPP::RSA::PrivateKey(params);
  publicKey = CryptoPP::RSA::PublicKey(params);

                }
                QString encrypt(QString data)
{
  std::string plaintext = data.trimmed().toStdString();
  std::string encryptedText;
  CryptoPP::RSAES_OAEP_SHA_Encryptor e( publicKey );
  CryptoPP::StringSource( plaintext, true, new CryptoPP::PK_EncryptorFilter( rng, e, new CryptoPP::StringSink( encryptedText )));
  return QString::fromStdString(encryptedText);
}

    QString decrypt(QString encryptData)
{
  std::string encryptedText = encryptedData.toStdString();
  std::string decryptedtext;
  CryptoPP::RSAES_OAEP_SHA_Decryptor d( privateKey );
  CryptoPP::StringSource( encryptedText, true, new CryptoPP::PK_DecryptorFilter( rng, d, new CryptoPP::StringSink( decryptedtext )));
  return QString::fromStdString(decryptedtext);
}
};

Encrypts, but does not want to return, with an error:

terminate called after throwing an instance of 'CryptoPP::InvalidArgument'
  what():  RSA/OAEP-MGF1(SHA-1): ciphertext length of 386 doesn't match the required length of 192 for this key

Answer 1

You can do without CryptoPP and use OpenSSL, here is an example https://github.com/JulyIghor/QtBitcoinTrader/blob/...