OpenSSL::X509::Extension#value_der

static VALUE
ossl_x509ext_get_value_der(VALUE obj)
{
    X509_EXTENSION *ext;
    ASN1_OCTET_STRING *value;

    GetX509Ext(obj, ext);
    if ((value = X509_EXTENSION_get_data(ext)) == NULL)
        ossl_raise(eX509ExtError, NULL);

    return rb_str_new((const char *)value->data, value->length);
}