Also allow custom IPs and domains to be looked-up

.htaccess

@@ -1,5 +1,10 @@
 RewriteEngine On
 RewriteBase /
+
 RewriteCond %{REQUEST_FILENAME} !-f
 RewriteCond %{REQUEST_FILENAME} !-d
-RewriteRule ^(.*)$ /index.php?m=$1
+RewriteRule ^([^/]+)/?$ /index.php?m=$1 [L]
+
+RewriteCond %{REQUEST_FILENAME} !-f
+RewriteCond %{REQUEST_FILENAME} !-d
+RewriteRule ^([^/]+)/([^/]+)/?$ index.php?m=$1&t=$2 [L]

README.md

@@ -4,6 +4,8 @@ A simple PHP script to tell a visitor's IP address and more information. This fi
 
 ## Plain return
 
+Example: [/][https://ip.nandus.net]
+
 When the script is properly installed, one can visit/curl/wget the website to just receive one's public IP address. This is very useful in combination with other scripts (check out my snap-dyndns packages for example).
 
 ```
@@ -13,6 +15,8 @@ max@laptop ~> wget -qO - ip.nandus.net
 
 ## Detailed return
 
+Example: [/myself](https://ip4.nandus.net/myself)
+
 Given the location of the script is `ip.example.com`, you can also receive more information about the HTTP headers or the IP's reverse lookup:
 
 ```
@@ -30,6 +34,17 @@ HOSTNAME: p5B3E4401.dip0.t-ipconnect.de
 IPv4 REVERSE LOOKUP: 91.62.68.1
 ```
 
+Additionally you will be given a whois output of your IP.
+
+## Custom DNS and IP lookup
+
+Example DNS: [/dns/example.com](https://ip.nandus.net/dns/example.com)
+Example IP: [/ip/8.8.8.8](https://ip.nandus.net/ip/8.8.8.8)
+
+You can also freely look up any hostname or IP. For domains, this will return a useful list of different DNS records (A, AAAA, NS, MX, TXT, SOA etc).
+
+You will also be given a whois output of the domain or IP.
+
 ## Ideal domain setup
 
 In order to use IPv4- and IPv6-only domains, you'll have to have control over the DNS nameserver records of your own domain.

index.php

@@ -2,16 +2,52 @@
 
 $config = include('config.php');
 
+$m = isset($_GET['m']) ? $_GET['m'] : false;
+$t = isset($_GET['t']) ? $_GET['t'] : false;
+
 // Define method by get parameter
 if(empty($_GET)) {
   $method = "simple";
+} elseif($m === "dns" && ! empty($t)) {
+  $method = "dns";
+} elseif($m === "ip" && ! empty($t)) {
+  $method = "ip";
+} elseif($m === "myself" && empty($t)) {
+  $method = "myself";
 } else {
-  $method = $_GET['m'];
+  $method = "unknown";
 }
 
 if($method === "simple") {  // simple
-  echo $_SERVER['REMOTE_ADDR'] . "\n";
+  $ip = $_SERVER['REMOTE_ADDR'];
-} elseif($method === "detailed" ) {  // detailed
+  echo $ip . "\n";
+  exit;
+} elseif($method === "myself" ) {  // detailed info about own IP
+  $ip = $_SERVER['REMOTE_ADDR'];
+  show_http_headers();
+  show_hostname($ip);
+  show_reverse($hostname);
+  show_whois($ip);
+} elseif($method === "ip" ) {  // detailed info an IP
+  $ip = $t;
+  show_hostname($ip);
+  show_reverse($hostname);
+  show_whois($ip);
+} elseif($method === "dns" ) {  // detailed info a host name
+  $hostname = $t;
+  show_reverse($hostname);
+  show_dnsrecords($hostname);
+  show_whois($hostname);
+} else if($method === "unknown") { // wrong URL
+  header("HTTP/1.1 301 Moved Permanently");
+  header("Location:/".$config->detailed_uri."");
+  exit;
+}
+footer();
+
+// HTTP HEADERS
+function show_http_headers() {
+  echo "<h2>YOUR HTTP HEADERS</h2>";
   readheader("REMOTE_ADDR");
   readheader("HTTP_X_FORWARDED_FOR");
   readheader("HTTP_USER_AGENT");
@@ -21,33 +57,129 @@ if($method === "simple") {  // simple
   readheader("HTTP_FORWARDED");
   readheader("HTTP_HOST");
   readheader("HTTP_URI");
-  $hostname = gethostbyaddr($_SERVER['REMOTE_ADDR']);
   echo "<br />";
-  echo "<strong>HOSTNAME</strong>: " . $hostname;
+}
-  echo "<br />";
+// DNS LOOKUP
-  echo "<strong>IPv4 REVERSE LOOKUP</strong>: " . implode(', ', gethostbynamel($hostname));
+function show_hostname($ip) {
-  echo "<br /><br /><strong>WHOIS:</strong>";
+  global $hostname;
-  $whois = shell_exec("whois " . $_SERVER['REMOTE_ADDR']);
+  $hostname = ip2hostname($ip);
+  echo "<strong>HOSTNAME</strong>: " . link_target($hostname);
+  echo "<br />\n";
+}
+// REVERSE IP4 LOOKUP
+function show_reverse($hostname) {
+  global $hostname;
+  $ip = hostname2ip($hostname);
+  echo "<strong>IPv4 REVERSE LOOKUP</strong>: " . link_target($ip);
+  echo "<br />\n";
+}
+// WHOIS
+function show_whois($target) {
+  echo "<h2>WHOIS</h2>\n";
+  if(preg_match('/^(?!\-)(?:[a-zA-Z\d\-]{0,62}[a-zA-Z\d]\.){1,126}(?!\d+)[a-zA-Z\d]{1,63}$/', $target)) {
+    // if domain, skip subdomains
+    preg_match('/[a-zA-Z\d]+\.[a-zA-Z\d]+$/', $target, $m);
+    $target = $m[0];
+  }
+  $whois = shell_exec("whois " . $target  );
   echo "<pre>"; print_r($whois); echo "</pre>";
-  echo "<br />";
+  echo "<br />\n";
+}
+// DNSRECORDS
+function show_dnsrecords($hostname) {
+  echo "<h2>DNS Records</h2>\n";
+  // A
+  $dnsrecords = dnsrecords($hostname, "DNS_A");
+  foreach($dnsrecords as $key=>$value) {
+    echo "<strong>" . $value['type'] . "</strong>: ";
+    echo link_target($value['ip']) . "<br />\n";
+  }
+  // AAAA
+  $dnsrecords = dnsrecords($hostname, "DNS_AAAA");
+  foreach($dnsrecords as $key=>$value) {
+    echo "<strong>" . $value['type'] . "</strong>: ";
+    echo link_target($value['ipv6']) . "<br />\n";
+  }
+  // MX
+  $dnsrecords = dnsrecords($hostname, "DNS_MX");
+  foreach($dnsrecords as $key=>$value) {
+    echo "<strong>" . $value['type'] . "</strong>: ";
+    echo link_target($value['target']) . " (" . $value['pri'] . ")<br />\n";
+  }
+  // NS
+  $dnsrecords = dnsrecords($hostname, "DNS_NS");
+  foreach($dnsrecords as $key=>$value) {
+    echo "<strong>" . $value['type'] . "</strong>: ";
+    echo link_target($value['target']) . "<br />\n";
+  }
+  // TXT
+  $dnsrecords = dnsrecords($hostname, "DNS_TXT");
+  foreach($dnsrecords as $key=>$value) {
+    echo "<strong>" . $value['type'] . "</strong>: ";
+    $i = 0;
+    foreach($value['entries'] as $entry) {
+      if($i !== 0){echo " | ";}
+      echo $entry;
+    }
+    echo "<br />\n";
+  }
+  // SOA
+  $dnsrecords = dnsrecords($hostname, "DNS_SOA");
+  foreach($dnsrecords as $key=>$value) {
+    echo "<strong>" . $value['type'] . "</strong>: ";
+    echo "" . $value['mname'] . " (mname), ";
+    echo "" . $value['rname'] . " (rname), ";
+    echo "" . $value['serial'] . " (serial)<br />\n";
+  }
   
-  echo "<br /><hr /><br />";
+  // OTHER
-  echo 'Plain IP address: <a href="//'.$config->ip4domain.'">IPv4</a> | <a href="//'.$config->ip6domain.'">IPv6</a>';
+  $dnsrecords = dnsrecords($hostname, "OTHER");
-  echo "<br />";
+  if(!empty($dnsrecords)) {
-  echo 'Detailed header info: <a href="//'.$config->ip4domain.'/'.$config->detailed_uri.'">IPv4</a> | <a href="//'.$config->ip6domain.'/'.$config->detailed_uri.'">IPv6</a>';
+    echo "<strong>Other DNS records</strong>:<br/>\n ";
-} else { // wrong URL
+    echo "<pre>"; print_r($dnsrecords); echo "</pre>";
-  header("HTTP/1.1 301 Moved Permanently");
+    echo "<br />\n";
-  header("Location:/".$config->detailed_uri."");
+  }
-  exit;
+}
+// PRINT FOOTER
+function footer() {
+  global $config;
+  echo "<br /><hr /><br />\n";
+  echo 'Your plain IP address: <a href="//'.$config->ip4domain.'">IPv4</a> | <a href="//'.$config->ip6domain.'">IPv6</a>';
+  echo "<br />\n";
+  echo 'Your detailed IP info: <a href="//'.$config->ip4domain.'/'.$config->detailed_uri.'">IPv4</a> | <a href="//'.$config->ip6domain.'/'.$config->detailed_uri.'">IPv6</a>';
 }
 
-function readheader($value)
+// HELPER FUNCTIONS
-{
+function readheader($value) {
   echo "<strong>" . $value . "</strong>: "; // show desired value 
   if(isset($_SERVER[$value])) {   // only if desired header has been delivered 
     echo $_SERVER[$value];
   }
-  echo "<br />";
+  echo "<br />\n";
+}
+function ip2hostname($ip) {
+  $hostname = gethostbyaddr($ip);
+  return $hostname;
+}
+function hostname2ip($hostname) {
+  $ip = implode(', ', gethostbynamel($hostname));
+  return $ip;
+}
+function dnsrecords($hostname, $record = "DNS_ALL") {
+  if($record === "OTHER") {
+    $dnsrecords = dns_get_record($hostname, DNS_ALL - DNS_A - DNS_AAAA - DNS_MX - DNS_NS - DNS_TXT - DNS_SOA);
+  } else {
+    $dnsrecords = dns_get_record($hostname, constant($record));
+  }
+  return $dnsrecords;
+}
+function link_target($target) {
+  if(filter_var($target, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4) || filter_var($target, FILTER_VALIDATE_IP, FILTER_FLAG_IPV6)) {
+    // target is an IP
+    return "<a href='/ip/" . $target . "/'>" . $target . "</a>";
+  } elseif(preg_match('/^(?!\-)(?:[a-zA-Z\d\-]{0,62}[a-zA-Z\d]\.){1,126}(?!\d+)[a-zA-Z\d]{1,63}$/', $target)) {
+    return "<a href='/dns/" . $target . "/'>" . $target . "</a>";
+  }
 }
 
 ?>