MDL-50907 antivirus: Implement data stream scanning default process.

lang/en/antivirus.php

@@ -26,6 +26,7 @@ $string['actantivirushdr'] = 'Available antivirus plugins';
 $string['antiviruses'] = 'Antivirus plugins';
 $string['antivirussettings'] = 'Manage antivirus plugins';
 $string['configantivirusplugins'] = 'Please choose the antivirus plugins you wish to use and arrange them in order of being applied.';
+$string['datastream'] = 'Data';
 $string['emailsubject'] = '{$a} :: Antivirus notification';
 $string['virusfound'] = '{$a->item} has been scanned by a virus checker and found to be infected!';
 

lib/classes/antivirus/manager.php

@@ -80,6 +80,23 @@ class manager {
         }
     }
 
+    /**
+     * Scan data steam using all enabled antiviruses, throws exception in case of infected data.
+     *
+     * @param string $data The varaible containing the data to scan.
+     * @throws \core\antivirus\scanner_exception If data is infected.
+     * @return void
+     */
+    public static function scan_data($data) {
+        $antiviruses = self::get_enabled();
+        foreach ($antiviruses as $antivirus) {
+            $result = $antivirus->scan_data($data);
+            if ($result === $antivirus::SCAN_RESULT_FOUND) {
+                throw new \core\antivirus\scanner_exception('virusfounduser', '', array('item' => get_string('datastream', 'antivirus')));
+            }
+        }
+    }
+
     /**
      * Returns instance of antivirus.
      *

lib/classes/antivirus/scanner.php

@@ -109,6 +109,26 @@ abstract class scanner {
      */
     public abstract function scan_file($file, $filename);
 
+    /**
+     * Scan data.
+     *
+     * By default it saves data variable content to file and then scans it using
+     * scan_file method, however if antivirus plugin permits scanning data directly,
+     * the method can be overridden.
+     *
+     * @param string $data The variable containing the data to scan.
+     * @return int Scanning result constants.
+     */
+    public function scan_data($data) {
+        // Prepare temp file.
+        $tempdir = make_request_directory();
+        $tempfile = $tempdir . DIRECTORY_SEPARATOR . rand();
+        file_put_contents($tempfile, $data);
+
+        // Perform a virus scan now.
+        return $this->scan_file($tempfile, get_string('datastream', 'antivirus'));
+    }
+
     /**
      * Email admins about antivirus scan outcomes.
      *