xref: /webtrees/app/Services/HtmlService.php (revision 8d897fd11a9a8845d8456cb9eaad33b9c9d5a225) 
1<?php
2
3/**
4 * webtrees: online genealogy
5 * Copyright (C) 2019 webtrees development team
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program. If not, see <http://www.gnu.org/licenses/>.
16 */
17declare(strict_types=1);
18
19namespace Fisharebest\Webtrees\Services;
20
21use HTMLPurifier;
22use HTMLPurifier_AttrDef_Enum;
23use HTMLPurifier_Config;
24
25/**
26 * Filter/sanitize HTML
27 */
28class HtmlService
29{
30    /**
31     * Take some dirty HTML (as provided by the user), and clean it before
32     * we save/display it.
33     *
34     * @param string $html
35     *
36     * @return string
37     */
38    public function sanitize(string $html): string
39    {
40        $config = HTMLPurifier_Config::createDefault();
41
42        $config->set('Cache.DefinitionImpl', null);
43
44        $config->set('HTML.TidyLevel', 'none'); // Only XSS cleaning now
45
46        $def = $config->getHTMLDefinition(true);
47
48        // Allow image maps.
49        $def->addAttribute('img', 'usemap', 'CDATA');
50
51        // Allow link targets.
52        $def->addAttribute('a', 'target', new HTMLPurifier_AttrDef_Enum(['_blank', '_self', '_target', '_top']));
53
54        $map = $def->addElement('map', 'Block', 'Flow', 'Common', [
55            'name'  => 'CDATA',
56            'id'    => 'ID',
57            'title' => 'CDATA',
58        ]);
59
60        $map->excludes = ['map' => true];
61
62        $area = $def->addElement('area', 'Block', 'Empty', 'Common', [
63            'name'      => 'CDATA',
64            'id'        => 'ID',
65            'alt'       => 'Text',
66            'coords'    => 'CDATA',
67            'accesskey' => 'Character',
68            'nohref'    => new HTMLPurifier_AttrDef_Enum(['nohref']),
69            'href'      => 'URI',
70            'shape'     => new HTMLPurifier_AttrDef_Enum(['rect', 'circle', 'poly', 'default']),
71            'tabindex'  => 'Number',
72        ]);
73
74        $area->excludes = ['area' => true];
75
76        $purifier = new HTMLPurifier($config);
77
78        return $purifier->purify($html);
79    }
80}
81