Making lookup.php PHP7 and IPv6 friendly.

Author: Markus-Go

README.md

@@ -10,6 +10,8 @@ you can <a
 href='https://github.com/Markus-Go/ip-countryside/blob/downloads/ip2country.zip?raw=true'>download 
 it here</a> (updated weekly).</b>
 
+A demo can be found <a href='https://www.goldiges.de/ip-countryside/' target='_BLANK'>here</a>. 
+
 Detailed Information
 --------------------
 
@@ -91,7 +93,7 @@ Copyright/ License/ Credits
 ---------------------------
 
 Copyright 2006-2007 Deutsches Forschungszentrum fuer Kuenstliche Intelligenz  
-Copyright 2008-2015 Markus Goldstein
+Copyright 2008-2020 Markus Goldstein
 
 This is free software. Licensed under the [Apache License, Version 2.0](LICENSE.txt).  
 There is NO WARRANTY, to the extent permitted by law.

lookup.php

@@ -2,7 +2,7 @@
 /**
  * Copyright 2007 Deutsches Forschungszentrum fuer Kuenstliche Intelligenz 
  * or its licensors, as applicable.
- * Copyright 2008-2015 Markus Goldstein
+ * Copyright 2008-2019 Markus Goldstein
  *
  * You may not use this file except under the terms of the accompanying license.
  * 
@@ -21,47 +21,53 @@
  *
 */
 
-if (!isset($_GET["ip"] ))
+if (!isset($_GET["ip"] )) {
     $ip = $_SERVER["REMOTE_ADDR"];
-else
+    // if IPv6, replace by server IP
+    if (!filter_var($ip, FILTER_VALIDATE_IP,FILTER_FLAG_IPV4)) {
+        $ip = "37.221.195.97"; // $_SERVER["SERVER_ADDR"];
+    }
+} else {
     $ip = strip_tags(trim($_GET["ip"]));
+}
 
+$dlText = "The database is generated weekly. It can be dowloaded as a <a href=\"https://github.com/Markus-Go/ip-countryside/raw/downloads/ip2country.zip\">zip-file</a>.<br>";
 $file = fopen("ip2country.db", "r") or die("Unable to open IP DB!");
-$last_modified = date("l, dS F Y, h:i a", filemtime("ip2country.zip"));
-$db_size = ceil(filesize("ip2country.zip")/1024);
-$count = 0;
-while(!feof($file)) {
-    list($start_ip[$count], $end_ip[$count], $country[$count]) = explode(" ",fgets($file));
-    $count++;
+if (file_exists("ip2country.zip")) {
+    $last_modified = date("l, dS F Y, h:i a", filemtime("ip2country.zip"));
+    $db_size = ceil(filesize("ip2country.zip")/1024);
+    $dlText = "The database is generated weekly and was last created on " . $last_modified . " (CEST).<br> It can be dowloaded as a <a href=\"ip2country.zip\">zip-file</a> (" . $db_size . " kb).<br/>";
 }
-    $error_code = 0;
-    list($a, $b, $c, $d) = explode(".",$ip);
 
-    if ((is_numeric($a) && is_numeric($b) && is_numeric($c) && is_numeric($d)) && 
-          (($a >= 0 && $a <= 255) && ($b >= 0 && $b <= 255) && ($c >= 0 && $c <= 255) && ($d >= 0 && $d <=255))){
-            $ipvalue = (int)$a*256*256*256 + (int)$b*256*256 + (int)$c*256 + (int)$d;
-        }
-    else {
-        $comment = "You entered an invalid IP address!";
-        fclose($file);    
-        $error_code = 1;
+while(!feof($file)) {
+    $line = fgets($file);
+    if (substr_count($line," ") == 2) {
+      list($start_ip[], $end_ip[], $country[]) = explode(" ",$line);
     }
+}
 
+$isValid = filter_var($ip, FILTER_VALIDATE_IP,FILTER_FLAG_IPV4);
+if ($isValid) {
+    list($a, $b, $c, $d) = explode(".",$ip);
+    $ipvalue = (int)$a*256*256*256 + (int)$b*256*256 + (int)$c*256 + (int)$d;
+} else {
+    $comment = "You entered an invalid IP address!";
+    fclose($file);    
+}
 
-    if ($error_code == 0) {
-        $cn = $country[binSearch(0,$count-1,$ipvalue)];
-        $cn_name = "Unknown";
-        $flag = strtolower($cn); 
-        $handle = fopen ("countries.txt","r");
+if ($isValid) {
+    $cn = $country[binSearch(0,count($start_ip),$ipvalue)];
+    $cn_name = "Unknown";
+    $flag = strtolower($cn); 
+    $handle = fopen ("countries.txt","r") or die("Unable to open countries.txt!");
 
-        while ( ($data = fgetcsv ($handle, 1000, ";")) !== FALSE ) {
-            if(trim($data[1]) == trim($cn)) {
-                $cn_name = ucfirst(strtolower($data[0]));
-            }
+    while ( ($data = fgetcsv ($handle, 1000, ";")) !== FALSE ) {
+        if(trim($data[1]) == trim($cn)) {
+            $cn_name = ucfirst(strtolower($data[0]));
         }
-
-        fclose($file);
     }
+    fclose($file);
+}
 
 function binSearch($start,$end,$search) {
     global $start_ip, $end_ip;
@@ -94,17 +100,16 @@ function ip2int($ip) {
 <H1>Country Lookup Demo</H1>
 <p>
 Here we provide an on-line demo of our <a href="https://github.com/Markus-Go/ip-countryside/" target="_BLANK">ip-countryside</a> project.<br>
-The database is generated weekly and was last created on <?php print $last_modified; ?> (CEST).<br>
-It can be dowloaded as a <a href="ip2country.zip">zip-file</a> (<?php echo $db_size; ?> kb).
-< For more details please contact <a href="https://www.goldiges.de/contact" target="_BLANK">Markus Goldstein</a>.
+<?php print $dlText ?>
+For more details please contact <a href="https://www.goldiges.de/contact" target="_BLANK">Markus Goldstein</a>.
 </p>
 <div align="center">
 <form method="get" action="<?php echo $_SERVER['SCRIPT_NAME'];?>">
 <font face="Arial" size="2"> IP Address: <input type="text" size="30" maxlength="15" name="ip" value="<?php print $ip; ?>"> </font><br />
 <input type="submit" value="Find"> 
 </form>
 </div>
-</br></br>
+<br/><br/>
 
 
 <table width="600" border="1" cellspacing="0" cellpadding="3" align="center">
@@ -116,7 +121,7 @@ function ip2int($ip) {
     <td><font face="Arial" size="2">Country Flag:</font></td>
     <td><font face="Arial" size="2"><b>
     <?php 
-    if ($error_code == 1 || empty($cn) ) {
+    if (!$isValid || empty($cn) ) {
         print ("-");
     }
     else
@@ -128,7 +133,7 @@ function ip2int($ip) {
     <td><font face="Arial" size="2">ISO Country Code: </font></td>
     <td><font face="Arial" size="2"><b>
     <?php
-    if ($error_code == 1 ||empty($cn)) {
+    if (!$isValid ||empty($cn)) {
         print ("-");
     }
     else
@@ -140,7 +145,7 @@ function ip2int($ip) {
     <td><font face="Arial" size="2">Country:</font> </td>
     <td><font face="Arial" size="2"><b>
     <?php 
-    if ($error_code == 1 || empty($cn)) {
+    if (!$isValid || empty($cn)) {
         print ("-");
     } 
     else 
@@ -152,7 +157,7 @@ function ip2int($ip) {
     <td><font face="Arial" size="2">Comment: </font> </td>
     <td><font face="Arial" size="2"><b>
     <?php 
-    if ($error_code == 1) {
+    if (!$isValid ) {
         print ($comment);
     }
     else if (empty($cn))