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c++rsacrypto++

How to encrypt/decrypt using RSA/OAEP if we have public key only

I'm learning Crypto++ library. I've read lot of examples but didn't find how to encrypt/decrypt plain text message when the program has access to public key only, when the program not generates the keys.

CryptoPP::RSA::PublicKey pubKey;
pubKey.Load(CryptoPP::StringSource(SSL_PUB_KEY, true, new CryptoPP::Base64Decoder()).Ref());
CryptoPP::RSAES_OAEP_SHA_Encryptor e(pubKey);

But what to do after that?

Solution

  • I've get how to do it. I missundertood what RandonGenerator is and I thought that I have to get it from a key.

    After that I do following:

    CryptoPP::AutoSeededRandomPool rng;
string cipher;
CryptoPP::StringSource ss1(stringToEncrypt, true, new CryptoPP::PK_EncryptorFilter(rng, e, new CryptoPP::StringSink(cipher)));

    now we have encrypted data in cipher