export

static VALUE
ossl_rsa_export(int argc, VALUE *argv, VALUE self)
{
    EVP_PKEY *pkey;
    BIO *out;
    const EVP_CIPHER *ciph = NULL;
    char *passwd = NULL;
    VALUE cipher, pass, str;

    GetPKeyRSA(self, pkey);

    rb_scan_args(argc, argv, "02", &cipher, &pass);

    if (!NIL_P(cipher)) {
        ciph = GetCipherPtr(cipher);
        if (!NIL_P(pass)) {
            StringValue(pass);
            if (RSTRING_LENINT(pass) < OSSL_MIN_PWD_LEN)
                ossl_raise(eOSSLError, "OpenSSL requires passwords to be at least four characters long");
            passwd = RSTRING_PTR(pass);
        }
    }
    if (!(out = BIO_new(BIO_s_mem()))) {
        ossl_raise(eRSAError, NULL);
    }
    if (RSA_HAS_PRIVATE(pkey->pkey.rsa)) {
        if (!PEM_write_bio_RSAPrivateKey(out, pkey->pkey.rsa, ciph,
                                         NULL, 0, ossl_pem_passwd_cb, passwd)) {
            BIO_free(out);
            ossl_raise(eRSAError, NULL);
        }
    } else {
        if (!PEM_write_bio_RSA_PUBKEY(out, pkey->pkey.rsa)) {
            BIO_free(out);
            ossl_raise(eRSAError, NULL);
        }
    }
    str = ossl_membio2str(out);

    return str;
}