formidable / classes / models / FrmFormState.php

FrmFormState.php in Formidable Forms – WordPress Form Builder for Contact Forms, Calculators, Quizzes & More 6.21, at classes/models/FrmFormState.php

247 lines 6.4 KB

Raw Download Zip

1	<?php
2
3	if ( ! defined( 'ABSPATH' ) ) {
4	die( 'You are not allowed to call this page directly.' );
5	}
6
7	/**
8	* Track form state in an encrypted form field.
9	* The state just holds some basic info, like if a [formidable] shortcode loaded
10	* with a title=1 or description=1 option.
11	*
12	* @since 6.2
13	*/
14	class FrmFormState {
15
16	/**
17	* @var FrmFormState
18	*/
19	private static $instance;
20
21	/**
22	* @var array
23	*/
24	private $state;
25
26	private function __construct() {
27	$this->state = array();
28	}
29
30	/**
31	* @param string $key
32	* @param mixed $value
33	* @return void
34	*/
35	public static function set_initial_value( $key, $value ) {
36	if ( is_callable( 'FrmProFormState::set_initial_value' ) ) {
37	// Let Pro handle state.
38	return;
39	}
40
41	self::maybe_initialize();
42	self::$instance->set( $key, $value );
43	}
44
45	/**
46	* @return bool true if just initialized.
47	*/
48	private static function maybe_initialize() {
49	if ( empty( self::$instance ) ) {
50	self::$instance = new self();
51	return true;
52	}
53	return false;
54	}
55
56	/**
57	* @param string $key
58	* @param mixed $value
59	* @return void
60	*/
61	public function set( $key, $value ) {
62	$this->state[ $key ] = $value;
63	}
64
65	/**
66	* @param string $key
67	* @param mixed $default
68	* @return mixed
69	*/
70	public static function get_from_request( $key, $default ) {
71	if ( self::maybe_initialize() ) {
72	self::get_state_from_request();
73	}
74	return self::$instance->get( $key, $default );
75	}
76
77	public function get( $key, $default ) {
78	if ( isset( $this->state[ $key ] ) ) {
79	return $this->state[ $key ];
80	}
81	return $default;
82	}
83
84	/**
85	* Render a basic version of the state field from Pro.
86	* This is required only when submitting with AJAX.
87	* It is used to track the value of a title=1\|0 or description=1\|0 option in a [formidable] shortcode.
88	*
89	* @param stdClass $form
90	* @return void
91	*/
92	public static function maybe_render_state_field( $form ) {
93	if ( is_callable( 'FrmProFormState::maybe_render_state_field' ) ) {
94	// Let Pro handle state when Pro is available.
95	// This way we can also avoid duplicate state fields if Pro isn't up to date.
96	return;
97	}
98
99	if ( empty( self::$instance ) && ! self::get_state_from_request() ) {
100	return;
101	}
102
103	$honeypot_field_id = self::$instance->get( 'honeypot_field_id', 0 );
104
105	if ( empty( $form->options['ajax_submit'] ) && ! $honeypot_field_id ) {
106	// This is only required for AJAX submit, or when the honeypot field is on the page.
107	return;
108	}
109
110	$state_title = ! empty( self::$instance->state['title'] ) ? 1 : 0;
111	$state_description = ! empty( self::$instance->state['description'] ) ? 1 : 0;
112	$settings_title = ! empty( $form->options['show_title'] ) ? 1 : 0;
113	$settings_description = ! empty( $form->options['show_description'] ) ? 1 : 0;
114
115	if ( $state_title === $settings_title && $state_description === $settings_description && ! $honeypot_field_id ) {
116	// Avoid state field if it matches form settings and there is no honeypot.
117	return;
118	}
119
120	self::$instance->render_state_field();
121	}
122
123	/**
124	* @return bool true if there is valid state data in the request.
125	*/
126	private static function get_state_from_request() {
127	$encrypted_state = FrmAppHelper::get_post_param( 'frm_state', '', 'sanitize_text_field' );
128	if ( ! $encrypted_state ) {
129	return false;
130	}
131	$secret = self::get_encryption_secret();
132	$decrypted_state = openssl_decrypt( $encrypted_state, 'AES-128-ECB', $secret );
133	if ( false === $decrypted_state ) {
134	return false;
135	}
136	$decoded_state = json_decode( $decrypted_state, true );
137	if ( ! is_array( $decoded_state ) ) {
138	return false;
139	}
140	foreach ( $decoded_state as $key => $value ) {
141	self::set_initial_value( self::decompressed_key( $key ), $value );
142	}
143	return true;
144	}
145
146	/**
147	* @return void
148	*/
149	public function render_state_field() {
150	if ( ! self::open_ssl_is_installed() ) {
151	return;
152	}
153	if ( ! $this->state && ! self::get_state_from_request() ) {
154	return;
155	}
156	$state_string = $this->get_state_string();
157	echo '<input name="frm_state" type="hidden" value="' . esc_attr( $state_string ) . '" />';
158	}
159
160	/**
161	* @return string
162	*/
163	private function get_state_string() {
164	if ( ! self::open_ssl_is_installed() ) {
165	return '';
166	}
167	$secret = self::get_encryption_secret();
168	$compressed_state = $this->compressed_state();
169	$json_encoded = json_encode( $compressed_state );
170	$encrypted = openssl_encrypt( $json_encoded, 'AES-128-ECB', $secret );
171	return $encrypted;
172	}
173
174	/**
175	* Returns true if open SSL is installed.
176	*
177	* @since 6.12
178	* @return bool
179	*/
180	private static function open_ssl_is_installed() {
181	return function_exists( 'openssl_encrypt' );
182	}
183
184	/**
185	* Return state but with shorter keys to use for the state string.
186	*
187	* @return array
188	*/
189	private function compressed_state() {
190	$compressed = array();
191	foreach ( $this->state as $key => $value ) {
192	$compressed[ self::compressed_key( $key ) ] = $value;
193	}
194	return $compressed;
195	}
196
197	/**
198	* Get the first character of a key to make the option take less space.
199	* "title" => "t".
200	* "description" => "d".
201	*
202	* @param string $key
203	* @return string
204	*/
205	private static function compressed_key( $key ) {
206	return $key[0];
207	}
208
209	/**
210	* Keys are truncated to a single character to make the state string smaller.
211	* Pro supports additional keys include "i" for include_fields and "g" for get params.
212	* To avoid conflicts, we should not add "i" or "g" in Lite for another state property.
213	*
214	* @param string $key
215	* @return string The full key name if one is found. If nothing is found, the $key param is passed back.
216	*/
217	private static function decompressed_key( $key ) {
218	switch ( $key ) {
219	case 'd':
220	return 'description';
221	case 't':
222	return 'title';
223	case 'h':
224	return 'honeypot_field_id';
225	}
226	return $key;
227	}
228
229	/**
230	* @return string
231	*/
232	private static function get_encryption_secret() {
233	$secret_key = get_option( 'frm_form_state_key' );
234
235	// If we already have the secret, send it back.
236	if ( false !== $secret_key ) {
237	return base64_decode( $secret_key ); // phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.obfuscation_base64_decode
238	}
239
240	// We don't have a secret, so let's generate one.
241	$secret_key = is_callable( 'sodium_crypto_secretbox_keygen' ) ? sodium_crypto_secretbox_keygen() : wp_generate_password( 32, true, true );
242	update_option( 'frm_form_state_key', base64_encode( $secret_key ), 'no' ); // phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.obfuscation_base64_encode
243
244	return $secret_key;
245	}
246	}
247