Added logic for LDAP user search

app/Controllers/Auth/LoginController.php

@@ -116,27 +116,47 @@ class LoginController extends AuthController
      * @param  string  $username
      * @param  string  $password
      * @param $dbUser
-     * @return bool
+     * @return bool|null
      * @throws \Slim\Exception\HttpNotFoundException
      * @throws \Slim\Exception\HttpUnauthorizedException
      */
     protected function ldapLogin(Request $request, string $username, string $password, $dbUser)
     {
+        // Build LDAP connection
         $server = $this->ldapConnect();
         if (!$server) {
             $this->session->alert(lang('ldap_cant_connect'), 'warning');
             return $dbUser;
         }
+        
+        //Get LDAP user's (R)DN
+        $userDN=$this->getLdapRdn($username, $password, $server);
+        if (!is_string($userDN)) {
+            return null;
+        }
+    
+        //Bind as user to validate password
         if (!@ldap_bind($server, $this->getLdapRdn($username), $password)) {
             if ($dbUser && !$dbUser->ldap) {
                 return $dbUser;
             }
             return null;
         }
+        
         if (!$dbUser) {
             $email = $username;
             if (!filter_var($username, FILTER_VALIDATE_EMAIL)) {
-                $search = ldap_search($server, $this->config['ldap']['base_domain'], ($this->config['ldap']['rdn_attribute'] ?? 'uid=').addslashes($username), ['mail']);
+                if (@is_string($this->config['ldap']['search_filter'])) {
+                    $search = ldap_read(
+                        $server,
+                        $userDN,
+                        'objectClass=*',
+                        array('mail',$this->config['ldap']['rdn_attribute'])
+                    );
+                          
+                } else {
+                    $search = ldap_search($server, $this->config['ldap']['base_domain'], ($this->config['ldap']['rdn_attribute'] ?? 'uid=').addslashes($username),['mail']);
+                }
                 $entry = ldap_first_entry($server, $search);
                 $email = @ldap_get_values($server, $entry, 'mail')[0] ?? platform_mail($username.rand(0, 100)); // if the mail is not set, generate a placeholder
             }