if (keygen.r_size.value == "custom") {
  if (keygen.r_custom_size.value != '') {
   keysize = keygen.r_custom_size.value;
  } else {
   alert("If you choose a custom size, you must enter a value!!");
  }
 } else {
 alert("choosing x");
 keysize = keygen.r_size.value;
 }


function garbage() {

 for (i = 0; i < keysize; i++) {
  keyval += random_character();
 }
 
 document.r_key.value = keyval;
}