get_the_user_ip.php

<?php

function get_the_user_ip() {
  if ( ! empty( $_SERVER['HTTP_CLIENT_IP'] ) ) {
    //check ip from share internet
    $ip = $_SERVER['HTTP_CLIENT_IP'];
  } elseif ( ! empty( $_SERVER['HTTP_X_FORWARDED_FOR'] ) ) {
    //to check ip is pass from proxy
    $ip = $_SERVER['HTTP_X_FORWARDED_FOR'];
  } else {
    $ip = $_SERVER['REMOTE_ADDR'];
  }
  return apply_filters( 'wpb_get_ip', $ip );
}
add_shortcode('show_ip', 'get_the_user_ip');