问使用openssl解码已使用java编码的数据。

EN

public final void rsaEncrypt(String data, String filePath) {
    try {
            Base64.Encoder encoder = Base64.getEncoder();
            PublicKey pubKey = readKeyFromFile("/" + Constants.PUBLIC_KEY_FILE_NAME, filePath);
            Cipher cipher = Cipher.getInstance(Constants.RSA_INSTANCE);
            cipher.init(Cipher.ENCRYPT_MODE, pubKey);
            byte[] cipherData = cipher.doFinal(data.getBytes("UTF-8"));
            writeToFile(Constants.ENCRYPTED_STRING_FILE_NAME, filePath, encoder.encodeToString(cipherData));
        } catch (BadPaddingException | InvalidKeyException | NoSuchPaddingException | NoSuchAlgorithmException
                | IllegalBlockSizeException | UnsupportedEncodingException e) {
            if (LOG.isErrorEnabled())
                LOG.error("Error encrypting String.", e);
            throw new EncryptionException("Error encrypting data", e);
        }
}

std::string prv =
    "-----BEGIN RSA PRIVATE KEY-----\n"
     // cut  key data

    "-----END RSA PRIVATE KEY-----\n";  
BIO *bio = BIO_new_mem_buf((void*)prv.c_str(), -1);
RSA* rsaPrivKey = PEM_read_bio_RSAPrivateKey(bio, NULL, NULL, NULL);

if (!rsaPrivKey)
    printf("ERROR: Could not load PRIVATE KEY!  PEM_read_bio_RSAPrivateKey FAILED: %s\n", ERR_error_string(ERR_get_error(), NULL));

BIO_free(bio);
// where enc[] holds the Base64 decoded data, but len becomes -1  and no data is decoded.
int len = RSA_private_decrypt(64,(unsigned char *)&enc, (unsigned char *)&dec, private_key_, RSA_PKCS1_PADDING);