diff --git a/README.md b/README.md
index 400f181..10105d9 100644
--- a/README.md
+++ b/README.md
@@ -29,7 +29,3 @@ Pour donner les droits à lanScan sous Linux, installer `sudo` au besoin, puis c
 ```
 www-data ALL = NOPASSWD: /usr/bin/nmap
 ````
-et modifier le fichier `config.php` avec :
-```php
-$use_sudo = true;
-```
diff --git a/config.php b/config.php
index e30194f..3a4bf70 100644
--- a/config.php
+++ b/config.php
@@ -13,12 +13,10 @@ $HOSTSCAN_OPTIONS = [
     'Pn'         => true,
     'F'          => true,
     'sV'         => true,
+    'T5'         => true,
     'stylesheet' => "$BASEDIR/hostScan.xsl"
 ];
 
-$refreshPeriod = 60;
-$use_sudo = false;
-
 $SCANSDIR = 'scans';
 $DATADIR  = '/usr/share/nmap';
 
diff --git a/filter_inputs.php b/filter_inputs.php
index 72912a0..42cfda4 100644
--- a/filter_inputs.php
+++ b/filter_inputs.php
@@ -1,5 +1,7 @@
 <?php
 
+include_once "config.php";
+
 $targetsListRegex        = "/^[\da-zA-Z-. \/]+$/";
 $hostsListRegex          = "/^[\da-zA-Z-.,:\/]+$/";
 $protocolePortsListRegex = "/^(([TU]:)?[0-9\-]+|[a-z\-]+)(,([TU]:)?[0-9\-]+|,[a-z\-]+)*$/";
@@ -7,12 +9,13 @@ $portsListRegex          = "/^([0-9\-]+|[a-z\-]+)(,[0-9\-]+|,[a-z\-]+)*$/";
 $tempoRegex              = "/^\d+[smh]?$/";
 $fileNameRegex           = '/^[^<>:"\/|?]+$/';
 
-$targets       = filter_input(INPUT_GET, 'targets', FILTER_VALIDATE_REGEXP, ['options' => ['regexp' => $targetsListRegex]]);
-$lan           = filter_input(INPUT_GET, 'lan', FILTER_VALIDATE_REGEXP, ['options' => ['regexp' => $targetsListRegex]]);
-$host          = filter_input(INPUT_GET, 'host', FILTER_VALIDATE_REGEXP, ['options' => ['regexp' => $targetsListRegex]]);
+$targets       = filter_input(INPUT_GET, 'targets', FILTER_VALIDATE_REGEXP, ['options' => ['regexp' => $targetsListRegex], "flags" => FILTER_NULL_ON_FAILURE]);
+$lan           = filter_input(INPUT_GET, 'lan', FILTER_VALIDATE_REGEXP, ['options' => ['regexp' => $targetsListRegex], "flags" => FILTER_NULL_ON_FAILURE]);
+$host          = filter_input(INPUT_GET, 'host', FILTER_VALIDATE_REGEXP, ['options' => ['regexp' => $targetsListRegex], "flags" => FILTER_NULL_ON_FAILURE]);
 $saveAs        = filter_input(INPUT_GET, 'saveAs', FILTER_VALIDATE_REGEXP, ['options' => ['regexp' => $fileNameRegex]]);
 $compareWith   = filter_input(INPUT_GET, 'compareWith', FILTER_VALIDATE_URL);
-$refreshPeriod = filter_input(INPUT_GET, 'refreshPeriod', FILTER_VALIDATE_INT, ['options' => ['min_range' => 0]]) ?? $refreshPeriod;
+$refreshPeriod = filter_input(INPUT_GET, 'refreshPeriod', FILTER_VALIDATE_INT, ['options' => ['min_range' => 0]]);
+$sudo          = filter_input(INPUT_GET, 'sudo', FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE);
 
 if ($lan) {
   $targets = $lan;
diff --git a/options.php b/options.php
index e4049c8..5022bf2 100755
--- a/options.php
+++ b/options.php
@@ -363,6 +363,13 @@ foreach (scandir($SCANSDIR) as $filename) {
               <div class="ui label">secondes</div>
             </div>
           </div>
+
+          <div class="inline field">
+            <div class="ui toggle checkbox" title="sudo">
+              <input type="checkbox" id="sudoCheckbox" name="sudo" <?= $sudo ?? false ? 'checked' : ''; ?>/>
+              <label for="sudoCheckbox">Exécuter en tant qu'administrateur</label>
+            </div>
+          </div>
         </div>
       </div>
 
diff --git a/scan.php b/scan.php
index dcc0c12..c315760 100755
--- a/scan.php
+++ b/scan.php
@@ -1,11 +1,10 @@
 <?php
 
-include_once 'config.php';
 include_once 'filter_inputs.php';
 
 if (!$targets) {
     http_response_code(400);
-    $errorMessage = 'Paramètre manquant : targets, lan ou host';
+    $errorMessage = "Valeur incorecte pour le paramètre <var>targets</var> : " . filter_input(INPUT_GET, "targets", FILTER_SANITIZE_FULL_SPECIAL_CHARS);
     include_once "options.php";
     die();
 }
@@ -16,7 +15,7 @@ $args = '';
 foreach ($inputs as $arg => $value) {
     if (is_null($value)) {
         http_response_code(400);
-        $errorMessage = "Valeur incorecte pour le paramètre $arg : " . filter_input(INPUT_GET, $arg, FILTER_SANITIZE_FULL_SPECIAL_CHARS);
+        $errorMessage = "Valeur incorecte pour le paramètre <var>$arg</var> : " . filter_input(INPUT_GET, $arg, FILTER_SANITIZE_FULL_SPECIAL_CHARS);
         include_once "options.php";
         die();
     } else if ($value) {
@@ -32,7 +31,7 @@ foreach ($inputs as $arg => $value) {
 
 $tempPath = tempnam(sys_get_temp_dir(), 'scan_').".xml";
 
-$command = ($use_sudo? "sudo " : "") . "nmap$args -oX '$tempPath' $targets 2>&1";
+$command = ($sudo? "sudo " : "") . "nmap$args -oX '$tempPath' $targets 2>&1";
 
 exec($command, $stderr, $retcode);