xref: /webtrees/app/Session.php (revision 4ebbf4ab91d79576e8ebdc761df5c39dec8019a3) 
1<?php
2/**
3 * webtrees: online genealogy
4 * Copyright (C) 2019 webtrees development team
5 * This program is free software: you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation, either version 3 of the License, or
8 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License
14 * along with this program. If not, see <http://www.gnu.org/licenses/>.
15 */
16declare(strict_types=1);
17
18namespace Fisharebest\Webtrees;
19
20use Illuminate\Support\Str;
21use Psr\Http\Message\ServerRequestInterface;
22use function array_map;
23use function explode;
24use function implode;
25use function parse_url;
26use function session_name;
27use function session_regenerate_id;
28use function session_register_shutdown;
29use function session_set_cookie_params;
30use function session_set_save_handler;
31use function session_start;
32use function session_status;
33use const PHP_URL_HOST;
34use const PHP_URL_PATH;
35use const PHP_URL_SCHEME;
36
37/**
38 * Session handling
39 */
40class Session
41{
42    /**
43     * Start a session
44     *
45     * @param ServerRequestInterface $request
46     *
47     * @return void
48     */
49    public static function start(ServerRequestInterface $request): void
50    {
51        // Store sessions in the database
52        session_set_save_handler(new SessionDatabaseHandler($request));
53
54        $url    = $request->getAttribute('request_uri');
55        $secure = parse_url($url, PHP_URL_SCHEME) === 'https';
56        $domain = parse_url($url, PHP_URL_HOST);
57        $path   = parse_url($url, PHP_URL_PATH);
58        $path   = explode('index.php', $path)[0];
59
60        // Paths containing UTF-8 characters need special handling.
61        $path = implode('/', array_map('rawurlencode', explode('/', $path)));
62
63        session_name('WT_SESSION');
64        session_register_shutdown();
65        session_set_cookie_params(0, $path, $domain, $secure, true);
66        session_start();
67
68        // A new session? Prevent session fixation attacks by choosing a new session ID.
69        if (!self::get('initiated')) {
70            self::regenerate(true);
71            self::put('initiated', true);
72        }
73    }
74
75    /**
76     * Read a value from the session
77     *
78     * @param string $name
79     * @param mixed  $default
80     *
81     * @return mixed
82     */
83    public static function get(string $name, $default = null)
84    {
85        return $_SESSION[$name] ?? $default;
86    }
87
88    /**
89     * After any change in authentication level, we should use a new session ID.
90     *
91     * @param bool $destroy
92     *
93     * @return void
94     */
95    public static function regenerate(bool $destroy = false): void
96    {
97        if ($destroy) {
98            self::clear();
99        }
100
101        if (session_status() === PHP_SESSION_ACTIVE) {
102            session_regenerate_id($destroy);
103        }
104    }
105
106    /**
107     * Remove all stored data from the session.
108     *
109     * @return void
110     */
111    public static function clear(): void
112    {
113        $_SESSION = [];
114    }
115
116    /**
117     * Write a value to the session
118     *
119     * @param string $name
120     * @param mixed  $value
121     *
122     * @return void
123     */
124    public static function put(string $name, $value): void
125    {
126        $_SESSION[$name] = $value;
127    }
128
129    /**
130     * Remove a value from the session
131     *
132     * @param string $name
133     *
134     * @return void
135     */
136    public static function forget(string $name): void
137    {
138        unset($_SESSION[$name]);
139    }
140
141    /**
142     * Cross-Site Request Forgery tokens - ensure that the user is submitting
143     * a form that was generated by the current session.
144     *
145     * @return string
146     */
147    public static function getCsrfToken(): string
148    {
149        if (!self::has('CSRF_TOKEN')) {
150            self::put('CSRF_TOKEN', Str::random(32));
151        }
152
153        return self::get('CSRF_TOKEN');
154    }
155
156    /**
157     * Does a session variable exist?
158     *
159     * @param string $name
160     *
161     * @return bool
162     */
163    public static function has(string $name): bool
164    {
165        return isset($_SESSION[$name]);
166    }
167}
168