Correctly handle IP addresses containing RFC 4007 scoping

Author: jbtronics

src/Entity/LogSystem/SecurityEventLogEntry.php

@@ -44,9 +44,9 @@
 use App\Entity\Base\AbstractDBElement;
 use App\Entity\UserSystem\User;
 use App\Events\SecurityEvents;
+use App\Helpers\IPAnonymizer;
 use Doctrine\ORM\Mapping as ORM;
 use InvalidArgumentException;
-use Symfony\Component\HttpFoundation\IpUtils;
 
 /**
  * This log entry is created when something security related to a user happens.
@@ -134,7 +134,7 @@ public function getIPAddress(): string
     public function setIPAddress(string $ip, bool $anonymize = true): self
     {
         if ($anonymize) {
-            $ip = IpUtils::anonymize($ip);
+            $ip = IPAnonymizer::anonymize($ip);
         }
         $this->extra['i'] = $ip;
 

src/Entity/LogSystem/UserLoginLogEntry.php

@@ -22,8 +22,9 @@
 
 namespace App\Entity\LogSystem;
 
+use App\Helpers\IPAnonymizer;
 use Doctrine\ORM\Mapping as ORM;
-use Symfony\Component\HttpFoundation\IpUtils;
+
 
 /**
  * This log entry is created when a user logs in.
@@ -59,7 +60,7 @@ public function getIPAddress(): string
     public function setIPAddress(string $ip, bool $anonymize = true): self
     {
         if ($anonymize) {
-            $ip = IpUtils::anonymize($ip);
+            $ip = IPAnonymizer::anonymize($ip);
         }
 
         $this->extra['i'] = $ip;

src/Entity/LogSystem/UserLogoutLogEntry.php

@@ -22,8 +22,8 @@
 
 namespace App\Entity\LogSystem;
 
+use App\Helpers\IPAnonymizer;
 use Doctrine\ORM\Mapping as ORM;
-use Symfony\Component\HttpFoundation\IpUtils;
 
 #[ORM\Entity]
 class UserLogoutLogEntry extends AbstractLogEntry
@@ -56,7 +56,7 @@ public function getIPAddress(): string
     public function setIPAddress(string $ip, bool $anonymize = true): self
     {
         if ($anonymize) {
-            $ip = IpUtils::anonymize($ip);
+            $ip = IPAnonymizer::anonymize($ip);
         }
 
         $this->extra['i'] = $ip;

src/Helpers/IPAnonymizer.php

@@ -0,0 +1,49 @@
+<?php
+/*
+ * This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
+ *
+ *  Copyright (C) 2019 - 2024 Jan Böhmer (https://github.com/jbtronics)
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Affero General Public License as published
+ *  by the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Affero General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Affero General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+declare(strict_types=1);
+
+
+namespace App\Helpers;
+
+use Symfony\Component\HttpFoundation\IpUtils;
+
+/**
+ * Utils to assist with IP anonymization.
+ * The IPUtils::anonymize has a certain edgecase with local-link addresses, which is handled here.
+ * See: https://github.com/Part-DB/Part-DB-server/issues/782
+ */
+final class IPAnonymizer
+{
+    public static function anonymize(string $ip): string
+    {
+        /**
+         * If the IP contains a % symbol, then it is a local-link address with scoping according to RFC 4007
+         * In that case, we only care about the part before the % symbol, as the following functions, can only work with
+         * the IP address itself. As the scope can leak information (containing interface name), we do not want to
+         * include it in our anonymized IP data.
+         */
+        if (str_contains($ip, '%')) {
+            $ip = substr($ip, 0, strpos($ip, '%'));
+        }
+
+        return IpUtils::anonymize($ip);
+    }
+}

tests/Helpers/IPAnonymizerTest.php

@@ -0,0 +1,44 @@
+<?php
+/*
+ * This file is part of Part-DB (https://github.com/Part-DB/Part-DB-symfony).
+ *
+ *  Copyright (C) 2019 - 2024 Jan Böhmer (https://github.com/jbtronics)
+ *
+ *  This program is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU Affero General Public License as published
+ *  by the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Affero General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Affero General Public License
+ *  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+namespace App\Tests\Helpers;
+
+use App\Helpers\IPAnonymizer;
+use PHPUnit\Framework\TestCase;
+
+class IPAnonymizerTest extends TestCase
+{
+
+    public function anonymizeDataProvider(): \Generator
+    {
+        yield ['127.0.0.0', '127.0.0.23'];
+        yield ['2001:0db8:85a3::', '2001:0db8:85a3:0000:0000:8a2e:0370:7334'];
+        //RFC 4007 format
+        yield ['fe80::', 'fe80::1fc4:15d8:78db:2319%enp4s0'];
+    }
+
+    /**
+     * @dataProvider anonymizeDataProvider
+     */
+    public function testAnonymize(string $expected, string $input): void
+    {
+        $this->assertSame($expected, IPAnonymizer::anonymize($input));
+    }
+}