class-nonce-handler.php — Jetpack – WP Security, Backup, Speed, & Growth 16.2-a.1

jetpack / jetpack_vendor / automattic / jetpack-connection / src / class-nonce-handler.php

jetpack / jetpack_vendor / automattic / jetpack-connection / src Last commit date

class-nonce-handler.php

213 lines

1	<?php
2	/**
3	* The nonce handler.
4	*
5	* @package automattic/jetpack-connection
6	*/
7
8	namespace Automattic\Jetpack\Connection;
9
10	/**
11	* The nonce handler.
12	*/
13	class Nonce_Handler {
14
15	/**
16	* How long the scheduled cleanup can run (in seconds).
17	* Can be modified using the filter `jetpack_connection_nonce_scheduled_cleanup_limit`.
18	*/
19	const SCHEDULED_CLEANUP_TIME_LIMIT = 5;
20
21	/**
22	* How many nonces should be removed per batch during the `clean_all()` run.
23	*/
24	const CLEAN_ALL_LIMIT_PER_BATCH = 1000;
25
26	/**
27	* Nonce lifetime in seconds.
28	*/
29	const LIFETIME = HOUR_IN_SECONDS;
30
31	/**
32	* The nonces used during the request are stored here to keep them valid.
33	* The property is static to keep the nonces accessible between the `Nonce_Handler` instances.
34	*
35	* @var array
36	*/
37	private static $nonces_used_this_request = array();
38
39	/**
40	* The database object.
41	*
42	* @var \wpdb
43	*/
44	private $db;
45
46	/**
47	* Initializing the object.
48	*/
49	public function __construct() {
50	global $wpdb;
51
52	$this->db = $wpdb;
53	}
54
55	/**
56	* Scheduling the WP-cron cleanup event.
57	*/
58	public function init_schedule() {
59	add_action( 'jetpack_clean_nonces', array( __CLASS__, 'clean_scheduled' ) );
60	if ( ! wp_next_scheduled( 'jetpack_clean_nonces' ) ) {
61	wp_schedule_event( time(), 'hourly', 'jetpack_clean_nonces' );
62	}
63	}
64
65	/**
66	* Reschedule the WP-cron cleanup event to make it start sooner.
67	*/
68	public function reschedule() {
69	wp_clear_scheduled_hook( 'jetpack_clean_nonces' );
70	wp_schedule_event( time(), 'hourly', 'jetpack_clean_nonces' );
71	}
72
73	/**
74	* Adds a used nonce to a list of known nonces.
75	*
76	* @param int $timestamp the current request timestamp.
77	* @param string $nonce the nonce value.
78	*
79	* @return bool whether the nonce is unique or not.
80	*/
81	public function add( $timestamp, $nonce ) {
82	if ( isset( static::$nonces_used_this_request[ "$timestamp:$nonce" ] ) ) {
83	return static::$nonces_used_this_request[ "$timestamp:$nonce" ];
84	}
85
86	// This should always have gone through Jetpack_Signature::sign_request() first to check $timestamp and $nonce.
87	$timestamp = (int) $timestamp;
88	$nonce = esc_sql( $nonce );
89
90	// Raw query so we can avoid races: add_option will also update.
91	$show_errors = $this->db->hide_errors();
92
93	$return = false;
94
95	// Running `try...finally` to make sure that we re-enable errors in case of an exception.
96	try {
97	$old_nonce = $this->db->get_row(
98	$this->db->prepare( "SELECT 1 FROM `{$this->db->options}` WHERE option_name = %s", "jetpack_nonce_{$timestamp}_{$nonce}" )
99	);
100
101	if ( $old_nonce === null ) {
102	$return = (bool) $this->db->query(
103	$this->db->prepare(
104	"INSERT INTO `{$this->db->options}` (`option_name`, `option_value`, `autoload`) VALUES (%s, %s, %s)",
105	"jetpack_nonce_{$timestamp}_{$nonce}",
106	time(),
107	'no'
108	)
109	);
110	}
111	} finally {
112	$this->db->show_errors( $show_errors );
113	}
114
115	static::$nonces_used_this_request[ "$timestamp:$nonce" ] = $return;
116
117	return $return;
118	}
119
120	/**
121	* Removing all existing nonces, or at least as many as possible.
122	* Capped at 20 seconds to avoid breaking the site.
123	*
124	* @param int $cutoff_timestamp All nonces added before this timestamp will be removed.
125	* @param int $time_limit How long the cleanup can run (in seconds).
126	*
127	* @return true
128	*/
129	public function clean_all( $cutoff_timestamp = PHP_INT_MAX, $time_limit = 20 ) {
130	// phpcs:ignore Generic.CodeAnalysis.ForLoopWithTestFunctionCall.NotAllowed
131	for ( $end_time = time() + $time_limit; time() < $end_time; ) {
132	$result = $this->delete( static::CLEAN_ALL_LIMIT_PER_BATCH, $cutoff_timestamp );
133
134	if ( ! $result ) {
135	break;
136	}
137	}
138
139	return true;
140	}
141
142	/**
143	* Scheduled clean up of the expired nonces.
144	*/
145	public static function clean_scheduled() {
146	/**
147	* Adjust the time limit for the scheduled cleanup.
148	*
149	* @since 9.5.0
150	*
151	* @param int $time_limit How long the cleanup can run (in seconds).
152	*/
153	$time_limit = apply_filters( 'jetpack_connection_nonce_cleanup_runtime_limit', static::SCHEDULED_CLEANUP_TIME_LIMIT );
154
155	( new static() )->clean_all( time() - static::LIFETIME, $time_limit );
156	}
157
158	/**
159	* Delete the nonces.
160	*
161	* @param int $limit How many nonces to delete.
162	* @param null\|int $cutoff_timestamp All nonces added before this timestamp will be removed.
163	*
164	* @return int\|false Number of removed nonces, or `false` if nothing to remove (or in case of a database error).
165	*/
166	public function delete( $limit = 10, $cutoff_timestamp = null ) {
167	global $wpdb;
168
169	$ids = $wpdb->get_col(
170	$wpdb->prepare(
171	"SELECT option_id FROM `{$wpdb->options}`"
172	. " WHERE `option_name` >= 'jetpack_nonce_' AND `option_name` < %s"
173	. ' LIMIT %d',
174	'jetpack_nonce_' . $cutoff_timestamp,
175	$limit
176	)
177	);
178
179	if ( ! is_array( $ids ) ) {
180	// There's an error and we can't proceed.
181	return false;
182	}
183
184	// Removing zeroes in case AUTO_INCREMENT of the options table is broken, and all ID's are zeroes.
185	$ids = array_filter( $ids );
186
187	if ( array() === $ids ) {
188	// There's nothing to remove.
189	return false;
190	}
191
192	$ids_fill = implode( ', ', array_fill( 0, count( $ids ), '%d' ) );
193
194	$args = $ids;
195	$args[] = 'jetpack_nonce_%';
196
197	// The Code Sniffer is unable to understand what's going on...
198	// phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared,WordPress.DB.PreparedSQLPlaceholders.ReplacementsWrongNumber
199	return $wpdb->query( $wpdb->prepare( "DELETE FROM `{$wpdb->options}` WHERE `option_id` IN ( {$ids_fill} ) AND option_name LIKE %s", $args ) );
200	}
201
202	/**
203	* Clean the cached nonces valid during the current request, therefore making them invalid.
204	*
205	* @return bool
206	*/
207	public static function invalidate_request_nonces() {
208	static::$nonces_used_this_request = array();
209
210	return true;
211	}
212	}
213