formidable / classes / models / FrmFormState.php

FrmFormState.php in Formidable Forms – WordPress Form Builder for Contact Forms, Calculators, Quizzes & More 6.28, at classes/models/FrmFormState.php

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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\|null
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	*
34	* @return void
35	*/
36	public static function set_initial_value( $key, $value ) {
37	if ( is_callable( 'FrmProFormState::set_initial_value' ) ) {
38	// Let Pro handle state.
39	return;
40	}
41
42	self::maybe_initialize();
43	self::$instance->set( $key, $value );
44	}
45
46	/**
47	* @return bool true if just initialized.
48	*/
49	private static function maybe_initialize() {
50	if ( empty( self::$instance ) ) {
51	self::$instance = new self();
52	return true;
53	}
54	return false;
55	}
56
57	/**
58	* @param string $key
59	* @param mixed $value
60	*
61	* @return void
62	*/
63	public function set( $key, $value ) {
64	$this->state[ $key ] = $value;
65	}
66
67	/**
68	* @param string $key
69	* @param mixed $default
70	*
71	* @return mixed
72	*/
73	public static function get_from_request( $key, $default ) {
74	if ( self::maybe_initialize() ) {
75	self::get_state_from_request();
76	}
77	return self::$instance->get( $key, $default );
78	}
79
80	/**
81	* @param string $key
82	* @param mixed $default
83	*
84	* @return mixed
85	*/
86	public function get( $key, $default ) {
87	return $this->state[ $key ] ?? $default;
88	}
89
90	/**
91	* Render a basic version of the state field from Pro.
92	* This is required only when submitting with AJAX.
93	* It is used to track the value of a title=1\|0 or description=1\|0 option in a [formidable] shortcode.
94	*
95	* @param stdClass $form
96	*
97	* @return void
98	*/
99	public static function maybe_render_state_field( $form ) {
100	if ( is_callable( 'FrmProFormState::maybe_render_state_field' ) ) {
101	// Let Pro handle state when Pro is available.
102	// This way we can also avoid duplicate state fields if Pro isn't up to date.
103	return;
104	}
105
106	if ( empty( self::$instance ) && ! self::get_state_from_request() ) {
107	return;
108	}
109
110	$honeypot_field_id = self::$instance->get( 'honeypot_field_id', 0 );
111
112	if ( empty( $form->options['ajax_submit'] ) && ! $honeypot_field_id ) {
113	// This is only required for AJAX submit, or when the honeypot field is on the page.
114	return;
115	}
116
117	$state_title = ! empty( self::$instance->state['title'] ) ? 1 : 0;
118	$state_description = ! empty( self::$instance->state['description'] ) ? 1 : 0;
119	$settings_title = ! empty( $form->options['show_title'] ) ? 1 : 0;
120	$settings_description = ! empty( $form->options['show_description'] ) ? 1 : 0;
121
122	if ( $state_title === $settings_title && $state_description === $settings_description && ! $honeypot_field_id ) {
123	// Avoid state field if it matches form settings and there is no honeypot.
124	return;
125	}
126
127	self::$instance->render_state_field();
128	}
129
130	/**
131	* @return bool true if there is valid state data in the request.
132	*/
133	private static function get_state_from_request() {
134	$encrypted_state = FrmAppHelper::get_post_param( 'frm_state', '', 'sanitize_text_field' );
135
136	if ( ! $encrypted_state ) {
137	return false;
138	}
139
140	$secret = self::get_encryption_secret();
141	$decrypted_state = openssl_decrypt( $encrypted_state, 'AES-128-ECB', $secret );
142
143	if ( false === $decrypted_state ) {
144	return false;
145	}
146
147	$decoded_state = json_decode( $decrypted_state, true );
148
149	if ( ! is_array( $decoded_state ) ) {
150	return false;
151	}
152
153	foreach ( $decoded_state as $key => $value ) {
154	self::set_initial_value( self::decompressed_key( $key ), $value );
155	}
156
157	return true;
158	}
159
160	/**
161	* @return void
162	*/
163	public function render_state_field() {
164	if ( ! self::open_ssl_is_installed() ) {
165	return;
166	}
167
168	if ( ! $this->state && ! self::get_state_from_request() ) {
169	return;
170	}
171
172	$state_string = $this->get_state_string();
173	echo '<input name="frm_state" type="hidden" value="' . esc_attr( $state_string ) . '" />';
174	}
175
176	/**
177	* @return string
178	*/
179	private function get_state_string() {
180	if ( ! self::open_ssl_is_installed() ) {
181	return '';
182	}
183
184	$secret = self::get_encryption_secret();
185	$compressed_state = $this->compressed_state();
186	$json_encoded = json_encode( $compressed_state );
187	return openssl_encrypt( $json_encoded, 'AES-128-ECB', $secret );
188	}
189
190	/**
191	* Returns true if open SSL is installed.
192	*
193	* @since 6.12
194	*
195	* @return bool
196	*/
197	private static function open_ssl_is_installed() {
198	return function_exists( 'openssl_encrypt' );
199	}
200
201	/**
202	* Return state but with shorter keys to use for the state string.
203	*
204	* @return array
205	*/
206	private function compressed_state() {
207	$compressed = array();
208
209	foreach ( $this->state as $key => $value ) {
210	$compressed[ self::compressed_key( $key ) ] = $value;
211	}
212
213	return $compressed;
214	}
215
216	/**
217	* Get the first character of a key to make the option take less space.
218	* "title" => "t".
219	* "description" => "d".
220	*
221	* @param string $key
222	*
223	* @return string
224	*/
225	private static function compressed_key( $key ) {
226	return $key[0];
227	}
228
229	/**
230	* Keys are truncated to a single character to make the state string smaller.
231	* Pro supports additional keys include "i" for include_fields and "g" for get params.
232	* To avoid conflicts, we should not add "i" or "g" in Lite for another state property.
233	*
234	* @param string $key
235	*
236	* @return string The full key name if one is found. If nothing is found, the $key param is passed back.
237	*/
238	private static function decompressed_key( $key ) {
239	switch ( $key ) {
240	case 'd':
241	return 'description';
242	case 't':
243	return 'title';
244	case 'h':
245	return 'honeypot_field_id';
246	}
247	return $key;
248	}
249
250	/**
251	* @return string
252	*/
253	private static function get_encryption_secret() {
254	$secret_key = get_option( 'frm_form_state_key' );
255
256	// If we already have the secret, send it back.
257	if ( false !== $secret_key ) {
258	return base64_decode( $secret_key ); // phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.obfuscation_base64_decode
259	}
260
261	// We don't have a secret, so let's generate one.
262	$secret_key = is_callable( 'sodium_crypto_secretbox_keygen' ) ? sodium_crypto_secretbox_keygen() : wp_generate_password( 32, true, true );
263	update_option( 'frm_form_state_key', base64_encode( $secret_key ), false ); // phpcs:ignore WordPress.PHP.DiscouragedPHPFunctions.obfuscation_base64_encode
264
265	return $secret_key;
266	}
267	}
268