interfaces
2 years ago
traits
2 years ago
match-not-regexp-rule.php
2 years ago
match-regexp-rule.php
2 years ago
must-contain-characters-rule.php
2 years ago
must-equal-rule.php
2 years ago
must-not-contain-characters-rule.php
2 years ago
rule.php
2 years ago
server-side-rule.php
5 days ago
ssr-callback-allowlist.php
5 days ago
server-side-rule.php
398 lines
| 1 | <?php |
| 2 | |
| 3 | |
| 4 | namespace JFB_Modules\Validation\Advanced_Rules; |
| 5 | |
| 6 | use JFB_Modules\Validation\Ssr; |
| 7 | use Jet_Form_Builder\Exceptions\Repository_Exception; |
| 8 | use JFB_Components\Repository\Repository_Pattern_Trait; |
| 9 | use JFB_Modules\Block_Parsers\Field_Data_Parser; |
| 10 | use JFB_Modules\Validation\Handlers\Validation_Handler; |
| 11 | use Jet_Form_Builder\Request\Request_Tools; |
| 12 | |
| 13 | // If this file is called directly, abort. |
| 14 | if ( ! defined( 'WPINC' ) ) { |
| 15 | die; |
| 16 | } |
| 17 | |
| 18 | class Server_Side_Rule extends Rule { |
| 19 | |
| 20 | use Repository_Pattern_Trait; |
| 21 | |
| 22 | /** |
| 23 | * Blacklist of dangerous functions that should never be allowed as callbacks. |
| 24 | * All values MUST be lowercase for case-insensitive comparison. |
| 25 | * |
| 26 | * @since 3.5.6.2 Security fix: expanded list and case-insensitive check |
| 27 | */ |
| 28 | const NOT_ALLOWED = array( |
| 29 | // Debug/output functions |
| 30 | 'var_dump', |
| 31 | 'var_export', |
| 32 | 'print_r', |
| 33 | 'sprintf', |
| 34 | 'printf', |
| 35 | // Command execution |
| 36 | 'shell_exec', |
| 37 | 'system', |
| 38 | 'exec', |
| 39 | 'passthru', |
| 40 | 'proc_open', |
| 41 | 'popen', |
| 42 | 'pcntl_exec', |
| 43 | 'proc_nice', |
| 44 | 'proc_terminate', |
| 45 | 'proc_close', |
| 46 | // Code execution |
| 47 | 'eval', |
| 48 | 'assert', |
| 49 | 'create_function', |
| 50 | 'call_user_func', |
| 51 | 'call_user_func_array', |
| 52 | 'preg_replace_callback', |
| 53 | 'array_map', |
| 54 | 'array_filter', |
| 55 | 'array_reduce', |
| 56 | 'usort', |
| 57 | 'uasort', |
| 58 | 'uksort', |
| 59 | 'array_walk', |
| 60 | 'array_walk_recursive', |
| 61 | // User mutations |
| 62 | 'wp_insert_user', |
| 63 | 'wp_update_user', |
| 64 | // File inclusion |
| 65 | 'include', |
| 66 | 'include_once', |
| 67 | 'require', |
| 68 | 'require_once', |
| 69 | // Serialization (object injection) |
| 70 | 'unserialize', |
| 71 | 'maybe_unserialize', |
| 72 | // File operations |
| 73 | 'file_get_contents', |
| 74 | 'file_put_contents', |
| 75 | 'fwrite', |
| 76 | 'fputs', |
| 77 | 'fopen', |
| 78 | 'readfile', |
| 79 | 'file', |
| 80 | 'fread', |
| 81 | 'fgets', |
| 82 | 'fgetc', |
| 83 | 'fgetcsv', |
| 84 | 'fpassthru', |
| 85 | 'move_uploaded_file', |
| 86 | 'copy', |
| 87 | 'rename', |
| 88 | 'unlink', |
| 89 | 'rmdir', |
| 90 | 'mkdir', |
| 91 | 'chmod', |
| 92 | 'chown', |
| 93 | 'chgrp', |
| 94 | // Network functions |
| 95 | 'curl_exec', |
| 96 | 'curl_multi_exec', |
| 97 | 'fsockopen', |
| 98 | 'pfsockopen', |
| 99 | 'stream_socket_client', |
| 100 | 'stream_socket_server', |
| 101 | // Dangerous PHP functions |
| 102 | 'parse_str', |
| 103 | 'extract', |
| 104 | 'putenv', |
| 105 | 'ini_set', |
| 106 | 'ini_alter', |
| 107 | 'dl', |
| 108 | 'mail', |
| 109 | 'header', |
| 110 | 'setcookie', |
| 111 | 'setrawcookie', |
| 112 | // POSIX functions |
| 113 | 'posix_kill', |
| 114 | 'posix_mkfifo', |
| 115 | 'posix_setpgid', |
| 116 | 'posix_setsid', |
| 117 | 'posix_setuid', |
| 118 | 'posix_setgid', |
| 119 | 'posix_seteuid', |
| 120 | 'posix_setegid', |
| 121 | // Apache functions |
| 122 | 'apache_child_terminate', |
| 123 | 'apache_setenv', |
| 124 | // Reflection/class manipulation |
| 125 | 'get_defined_functions', |
| 126 | 'get_defined_vars', |
| 127 | 'get_defined_constants', |
| 128 | 'phpinfo', |
| 129 | 'highlight_file', |
| 130 | 'show_source', |
| 131 | 'php_strip_whitespace', |
| 132 | 'get_cfg_var', |
| 133 | 'get_current_user', |
| 134 | 'getmyuid', |
| 135 | 'getmypid', |
| 136 | 'getenv', |
| 137 | // WordPress data/state mutation (added 3.6.5.3 — not blocked by the allowlist |
| 138 | // alone, since the allowlist only records what an editor once typed, not what |
| 139 | // is actually safe to expose to an unauthenticated caller's argument). |
| 140 | 'wp_delete_file', |
| 141 | 'wp_delete_post', |
| 142 | 'wp_delete_attachment', |
| 143 | 'wp_trash_post', |
| 144 | 'delete_option', |
| 145 | 'delete_site_option', |
| 146 | 'delete_post_meta', |
| 147 | 'delete_user_meta', |
| 148 | 'delete_metadata', |
| 149 | 'update_option', |
| 150 | 'add_option', |
| 151 | 'update_site_option', |
| 152 | 'update_post_meta', |
| 153 | 'update_user_meta', |
| 154 | 'wp_set_password', |
| 155 | 'wp_delete_user', |
| 156 | 'add_user_meta', |
| 157 | 'add_role', |
| 158 | 'remove_role', |
| 159 | 'wp_update_post', |
| 160 | 'wp_insert_post', |
| 161 | 'do_shortcode', |
| 162 | 'do_action', |
| 163 | 'apply_filters', |
| 164 | 'deactivate_plugins', |
| 165 | 'activate_plugin', |
| 166 | 'switch_to_blog', |
| 167 | 'restore_current_blog', |
| 168 | 'wp_remote_get', |
| 169 | 'wp_remote_post', |
| 170 | 'wp_remote_request', |
| 171 | 'wp_safe_remote_get', |
| 172 | 'wp_safe_remote_post', |
| 173 | 'wp_safe_remote_request', |
| 174 | 'wp_remote_head', |
| 175 | 'delete_transient', |
| 176 | 'delete_site_transient', |
| 177 | 'set_transient', |
| 178 | 'set_site_transient', |
| 179 | 'wp_cache_add', |
| 180 | 'wp_cache_set', |
| 181 | 'wp_cache_replace', |
| 182 | 'wp_cache_delete', |
| 183 | 'wp_cache_flush', |
| 184 | 'wp_cache_flush_group', |
| 185 | 'wp_cache_flush_runtime', |
| 186 | 'wp_cache_incr', |
| 187 | 'wp_cache_decr', |
| 188 | 'clean_post_cache', |
| 189 | 'clean_term_cache', |
| 190 | 'clean_comment_cache', |
| 191 | 'flush_rewrite_rules', |
| 192 | 'wp_delete_comment', |
| 193 | 'wp_trash_comment', |
| 194 | 'wp_delete_term', |
| 195 | 'wp_remove_object_terms', |
| 196 | 'wp_die', |
| 197 | ); |
| 198 | |
| 199 | /** |
| 200 | * Function names that ship with the plugin as selectable "Server-Side callback" |
| 201 | * options and are safe by construction — they never reach `call_user_func()`, |
| 202 | * `validate()` resolves them straight to a `Ssr\Base_Validation_Callback` instance. |
| 203 | * Kept separate from the allowlist option so a fresh install already offers them. |
| 204 | * |
| 205 | * @since 3.6.5.2 |
| 206 | */ |
| 207 | const BUILTIN_ALLOWED = array(); |
| 208 | |
| 209 | public function __construct() { |
| 210 | $this->rep_install(); |
| 211 | } |
| 212 | |
| 213 | /** |
| 214 | * Whether $function_name resolves to one of the built-in callbacks (registered via |
| 215 | * `rep_instances()`/`get_id()`), i.e. it will never be passed to `call_user_func()`. |
| 216 | * |
| 217 | * @since 3.6.5.2 |
| 218 | */ |
| 219 | public static function is_builtin_callback( string $function_name ): bool { |
| 220 | foreach ( ( new self() )->rep_instances() as $callback ) { |
| 221 | if ( $callback->get_id() === $function_name ) { |
| 222 | return true; |
| 223 | } |
| 224 | } |
| 225 | |
| 226 | return false; |
| 227 | } |
| 228 | |
| 229 | public function rep_instances(): array { |
| 230 | return apply_filters( |
| 231 | 'jet-form-builder/validation-callbacks', |
| 232 | array( |
| 233 | new Ssr\Is_User_Login_Unique(), |
| 234 | new Ssr\Is_User_Email_Unique(), |
| 235 | new Ssr\Is_Field_Value_Unique(), |
| 236 | new Ssr\Is_User_Password_Valid(), |
| 237 | ) |
| 238 | ); |
| 239 | } |
| 240 | |
| 241 | public function get_id(): string { |
| 242 | return 'ssr'; |
| 243 | } |
| 244 | |
| 245 | public function get_label(): string { |
| 246 | return __( 'Server-Side callback', 'jet-form-builder' ); |
| 247 | } |
| 248 | |
| 249 | public function validate_field( Field_Data_Parser $parser ) { |
| 250 | $function_name = $this->get_setting( 'value' ); |
| 251 | |
| 252 | if ( ! $this->validate_submission_signature( $parser ) ) { |
| 253 | $parser->collect_error( 'rule:ssr:invalid_signature', $this->get_setting( 'message' ) ); |
| 254 | |
| 255 | return; |
| 256 | } |
| 257 | |
| 258 | $is_valid = $this->validate( $parser, $function_name ); |
| 259 | |
| 260 | if ( $is_valid ) { |
| 261 | return; |
| 262 | } |
| 263 | |
| 264 | $parser->collect_error( 'rule:ssr:' . $function_name, $this->get_setting( 'message' ) ); |
| 265 | } |
| 266 | |
| 267 | /** |
| 268 | * @return Ssr\Base_Validation_Callback[] |
| 269 | */ |
| 270 | public function get_callbacks(): array { |
| 271 | return $this->rep_get_items(); |
| 272 | } |
| 273 | |
| 274 | protected function validate( Field_Data_Parser $parser, string $function_name ): bool { |
| 275 | try { |
| 276 | /** @var Ssr\Base_Validation_Callback $callback */ |
| 277 | $callback = $this->rep_get_item( $function_name ); |
| 278 | } catch ( Repository_Exception $exception ) { |
| 279 | return $this->validate_custom( $parser, $function_name ); |
| 280 | } |
| 281 | |
| 282 | return $callback->is_valid_with_parser( $parser ); |
| 283 | } |
| 284 | |
| 285 | protected function validate_submission_signature( Field_Data_Parser $parser ): bool { |
| 286 | $rule_index = $this->get_setting( '_rule_index' ); |
| 287 | |
| 288 | if ( false === $rule_index ) { |
| 289 | return true; |
| 290 | } |
| 291 | |
| 292 | return Validation_Handler::validate_main_signature( |
| 293 | Request_Tools::get_request(), |
| 294 | jet_fb_handler()->get_form_id(), |
| 295 | explode( '.', $parser->get_scoped_name() ), |
| 296 | absint( $rule_index ) |
| 297 | ); |
| 298 | } |
| 299 | |
| 300 | protected function validate_custom( Field_Data_Parser $parser, string $function_name ): bool { |
| 301 | $name = $this->validate_callback( $function_name ); |
| 302 | |
| 303 | if ( ! $name ) { |
| 304 | return false; |
| 305 | } |
| 306 | |
| 307 | return (bool) call_user_func( $name, $parser->get_value(), $parser->get_context() ); |
| 308 | } |
| 309 | |
| 310 | /** |
| 311 | * Validate callback function name for security. |
| 312 | * |
| 313 | * Two checks apply, both must pass: |
| 314 | * 1. Denylist (`NOT_ALLOWED`) — kept as defense in depth, blocks known-catastrophic |
| 315 | * functions outright even if the allowlist below is ever misconfigured. |
| 316 | * 2. Allowlist — a function must be explicitly known-safe: either shipped with the |
| 317 | * plugin, collected from a form an editor actually saved with this callback |
| 318 | * configured (`Ssr_Callback_Allowlist`), or added by a site via the |
| 319 | * `jet-form-builder/ssr-validation/allowed-callbacks` filter. A denylist alone |
| 320 | * cannot enumerate every dangerous function in PHP core + WordPress core + active |
| 321 | * plugins, so functions unknown to either list are rejected by default. |
| 322 | * |
| 323 | * @since 3.5.6.2 Denylist introduced. |
| 324 | * @since 3.6.5.2 Allowlist enforcement added. |
| 325 | * |
| 326 | * @param string $function_name The function name to validate. |
| 327 | * |
| 328 | * @return string Empty string if invalid, function name if valid. |
| 329 | */ |
| 330 | protected function validate_callback( string $function_name ): string { |
| 331 | $name = preg_replace( '/[^\w]/i', '', $function_name ); |
| 332 | |
| 333 | if ( $name !== $function_name ) { |
| 334 | return ''; |
| 335 | } |
| 336 | |
| 337 | // Case-insensitive checks (PHP function names are case-insensitive). |
| 338 | $name_lower = strtolower( $name ); |
| 339 | |
| 340 | if ( in_array( $name_lower, self::NOT_ALLOWED, true ) ) { |
| 341 | return ''; |
| 342 | } |
| 343 | |
| 344 | if ( ! function_exists( $name ) ) { |
| 345 | return ''; |
| 346 | } |
| 347 | |
| 348 | $allowed = $this->get_allowed_callbacks(); |
| 349 | |
| 350 | if ( ! in_array( $name_lower, $allowed, true ) ) { |
| 351 | Ssr_Callback_Allowlist::refresh_allowed_callbacks_for_form( |
| 352 | (int) jet_fb_handler()->get_form_id() |
| 353 | ); |
| 354 | $allowed = $this->get_allowed_callbacks(); |
| 355 | } |
| 356 | |
| 357 | return in_array( $name_lower, $allowed, true ) ? $name : ''; |
| 358 | } |
| 359 | |
| 360 | /** |
| 361 | * Scoped to the form actually being submitted — a function name configured on one |
| 362 | * form is never usable from another form, even though both may have been saved by |
| 363 | * the same (already admin-gated) capability. See `Ssr_Callback_Allowlist` for why |
| 364 | * this matters: the allowlist only records "some editor typed this name once", not |
| 365 | * "this function is safe everywhere", so it must not widen past the form an editor |
| 366 | * actually approved it on. |
| 367 | * |
| 368 | * @since 3.6.5.2 |
| 369 | * @since 3.6.5.3 Scoped per-form instead of site-wide. |
| 370 | * |
| 371 | * @return string[] Lowercased function names allowed to run via `call_user_func()`. |
| 372 | */ |
| 373 | protected function get_allowed_callbacks(): array { |
| 374 | $allowed = array_merge( |
| 375 | self::BUILTIN_ALLOWED, |
| 376 | Ssr_Callback_Allowlist::get_allowed_callbacks_for_form( |
| 377 | (int) jet_fb_handler()->get_form_id() |
| 378 | ) |
| 379 | ); |
| 380 | |
| 381 | $allowed = (array) apply_filters( |
| 382 | 'jet-form-builder/ssr-validation/allowed-callbacks', |
| 383 | array_values( array_unique( array_map( 'strtolower', $allowed ) ) ), |
| 384 | (int) jet_fb_handler()->get_form_id() |
| 385 | ); |
| 386 | |
| 387 | $allowed = array_map( |
| 388 | static function ( $callback ): string { |
| 389 | return is_string( $callback ) ? strtolower( $callback ) : ''; |
| 390 | }, |
| 391 | $allowed |
| 392 | ); |
| 393 | |
| 394 | return array_values( array_unique( array_filter( $allowed ) ) ); |
| 395 | } |
| 396 | |
| 397 | } |
| 398 |