vigilante / includes / class-htaccess-manager.php

class-htaccess-manager.php in Vigilant – 100% Free Security Suite: Firewall, 2FA, Login, Headers, Scanner… 2.11.12, at includes/class-htaccess-manager.php

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1	<?php
2	/**
3	* HTAccess Manager Class
4	*
5	* Centralized, safe management of .htaccess modifications
6	* Used by both Firewall and Security Headers modules
7	*
8	* @package Vigilante
9	*/
10
11	// Prevent direct access
12	if ( ! defined( 'ABSPATH' ) ) {
13	exit;
14	}
15
16	/**
17	* Class Vigilante_Htaccess_Manager
18	*
19	* Provides atomic, safe operations on .htaccess file
20	*/
21	class Vigilante_Htaccess_Manager {
22
23	/**
24	* Singleton instance
25	*
26	* @var Vigilante_Htaccess_Manager
27	*/
28	private static $instance = null;
29
30	/**
31	* Option where the server software seen in a web request is remembered
32	*
33	* WP-CLI has no request to look at, so the detection made from the web is
34	* kept here and used as the fallback. See is_apache().
35	*
36	* @since 2.9.9
37	*
38	* @var string
39	*/
40	const SERVER_OPTION = 'vigilante_server_software';
41
42	/**
43	* Path to .htaccess file
44	*
45	* @var string
46	*/
47	private $htaccess_path;
48
49	/**
50	* Known block markers (start => end)
51	*
52	* @var array
53	*/
54	/**
55	* Option holding the write lock, and how long a held lock is believed.
56	*
57	* @since 2.10.0
58	*/
59	const LOCK_OPTION = 'vigilante_htaccess_write_lock';
60	const LOCK_TIMEOUT = 30;
61
62	/**
63	* The single-slot rollback buffer, cleared at the end of every operation.
64	*
65	* @since 2.10.0
66	*/
67	const BACKUP_OPTION = 'vigilante_htaccess_backup';
68
69	private $known_blocks = array(
70	'# BEGIN Vigilante Protection' => '# END Vigilante Protection',
71	'# BEGIN Vigilante Security Headers' => '# END Vigilante Security Headers',
72	'# BEGIN WordPress' => '# END WordPress',
73	);
74
75	/**
76	* Get singleton instance
77	*
78	* @return Vigilante_Htaccess_Manager
79	*/
80	public static function get_instance() {
81	if ( null === self::$instance ) {
82	self::$instance = new self();
83	}
84	return self::$instance;
85	}
86
87	/**
88	* Constructor
89	*/
90	private function __construct() {
91	$this->htaccess_path = ABSPATH . '.htaccess';
92	}
93
94	/**
95	* Add or update a block in .htaccess
96	*
97	* @param string $marker_start Start marker (e.g. "# BEGIN Vigilante Protection").
98	* @param string $marker_end End marker (e.g. "# END Vigilante Protection").
99	* @param string $rules Rules content (without markers).
100	* @param string $position Where to add: 'top' or 'before_wordpress'.
101	* @return bool\|WP_Error
102	*/
103	public function add_block( $marker_start, $marker_end, $rules, $position = 'top', $automatic = false ) {
104	/*
105	* On a network the root .htaccess is shared by every site, so only the
106	* main site writes it.
107	*
108	* Which question to ask depends on who is asking. A write a person
109	* started from a settings screen has to clear the capability too, so one
110	* site's administrator cannot overwrite what the network decided. A write
111	* Vigilant performs by itself only has to come from the right site: it
112	* makes no decision, and demanding a capability of it means demanding one
113	* of whichever visitor happened to trigger the request, which nobody has.
114	*
115	* Getting that distinction wrong is what shipped in 2.10.0, and it is why
116	* no network ever had its .htaccess refreshed after an update.
117	*/
118	$allowed = $automatic
119	? Vigilante_Settings::owns_shared_files()
120	: Vigilante_Settings::can_write_shared_files();
121
122	if ( ! $allowed ) {
123	return new WP_Error( 'network_not_owner', Vigilante_Settings::get_shared_files_notice() );
124	}
125
126	/*
127	* One writer at a time. maybe_sync_server_files() runs on init, on every
128	* request, so the first visitors after an update can enter this
129	* read-modify-write at the same moment. Two concurrent writers of
130	* different blocks is the case that bites: the second one read the file
131	* before the first one wrote, so its write drops the block the first one
132	* had just added.
133	*/
134	if ( ! $this->acquire_lock() ) {
135	return new WP_Error( 'locked', __( 'Another process is writing .htaccess right now', 'vigilante' ) );
136	}
137
138	try {
139	// Read current content
140	$original = $this->read_file();
141
142	/*
143	* read_file() answers '' when there is no file and false when there
144	* is one PHP cannot read. Until 2.11.8 both became an empty string
145	* here, so a .htaccess that PHP could write but not read was replaced
146	* whole by the Vigilant block, and every other rule in it was lost.
147	*/
148	if ( false === $original ) {
149	return new WP_Error( 'read_failed', __( '.htaccess could not be read, so it was left as it is.', 'vigilante' ) );
150	}
151
152	/*
153	* A block that has lost a marker would take the rest of the file with
154	* it. The other known blocks are asked too: validate_content() below
155	* refuses any result where one of them is unmatched, and saying why
156	* here keeps that refusal from reading as a write failure worth
157	* retrying every hour.
158	*/
159	$whole = $this->blocks_are_whole( $original, $marker_start, $marker_end );
160	foreach ( $this->known_blocks as $known_start => $known_end ) {
161	$whole = $whole && $this->blocks_are_whole( $original, $known_start, $known_end );
162	}
163	if ( ! $whole ) {
164	return new WP_Error( 'block_incomplete', __( 'A Vigilant block in .htaccess is missing one of its markers, so the file was left as it is.', 'vigilante' ) );
165	}
166
167	// Create backup before modification
168	if ( ! empty( $original ) ) {
169	$this->create_backup( $original );
170	}
171
172	// Remove existing block if present
173	$content = $this->remove_block_from_content( $original, $marker_start, $marker_end );
174
175	// Build new block
176	$block = $marker_start . "\n" . $rules . "\n" . $marker_end;
177
178	// Insert at correct position
179	$new_content = $this->insert_block( $content, $block, $position );
180
181	// Validate result
182	if ( ! $this->validate_content( $new_content ) ) {
183	return new WP_Error( 'invalid_result', __( 'Resulting .htaccess would be invalid', 'vigilante' ) );
184	}
185
186	// Write file
187	if ( ! $this->write_file( $new_content ) ) {
188	return new WP_Error( 'write_failed', __( 'Failed to write .htaccess', 'vigilante' ) );
189	}
190
191	/*
192	* Read back what actually landed. Writing is not the same as having
193	* written: a truncated write, a full disk or a filesystem layer that
194	* quietly mangles the content would otherwise leave the site serving a
195	* broken .htaccess with nobody the wiser, which on this file means a
196	* 500 on every page. If the file on disk does not validate, or does
197	* not contain the block that was just added, put back exactly what was
198	* there before and report the failure instead of walking away.
199	*/
200	$written = $this->read_file();
201
202	if ( false === $written
203	\|\| ! $this->validate_content( $written )
204	\|\| false === strpos( $written, $marker_start )
205	) {
206	if ( '' !== $original ) {
207	$this->write_file( $original );
208	}
209
210	return new WP_Error( 'verify_failed', __( 'The .htaccess was written but did not read back as expected, so the previous content was restored', 'vigilante' ) );
211	}
212
213	// Record the block as Vigilant's own. The integrity scan leaves
214	// out of its hash only the blocks whose fingerprint is recorded,
215	// so anything else carrying these markers is still checked.
216	if ( class_exists( 'Vigilante_File_Integrity' ) ) {
217	Vigilante_File_Integrity::remember_owned_block( '.htaccess', $marker_start, $block );
218	}
219
220	return true;
221	} finally {
222	// No .htaccess content, which may hold secrets, is left in the
223	// options table after the operation. Since 2.11.9.
224	$this->clear_backup();
225	$this->release_lock();
226	}
227	}
228
229	/**
230	* Take the write lock, or fail if another process holds it.
231	*
232	* Until 2.11.8 this relied on add_option() being atomic, and it is not: it
233	* runs INSERT ... ON DUPLICATE KEY UPDATE, so two writers arriving together
234	* both believed they held the lock. See Vigilante_Settings::acquire_option_lock().
235	* A lock older than the timeout still counts as abandoned and is taken over.
236	*
237	* @since 2.10.0
238	* @return bool
239	*/
240	private function acquire_lock() {
241	return Vigilante_Settings::acquire_option_lock( self::LOCK_OPTION, self::LOCK_TIMEOUT );
242	}
243
244	/**
245	* Release the write lock.
246	*
247	* @since 2.10.0
248	*/
249	private function release_lock() {
250	Vigilante_Settings::release_option_lock( self::LOCK_OPTION );
251	}
252
253	/**
254	* Drop the integrity scan's record of a block Vigilant no longer has in the file
255	*
256	* @since 2.11.5
257	*
258	* @param string $marker_start Start marker of the block.
259	*/
260	private function forget_owned_block( $marker_start ) {
261	if ( class_exists( 'Vigilante_File_Integrity' ) ) {
262	Vigilante_File_Integrity::forget_owned_blocks( '.htaccess', $marker_start );
263	}
264	}
265
266	/**
267	* Remove a block from .htaccess
268	*
269	* Takes the same write lock as add_block(): until 2.11.0 this
270	* read-modify-write ran unlocked, so a removal racing an addition of a
271	* different block could drop the block that had just been written (S5).
272	*
273	* @param string $marker_start Start marker.
274	* @param string $marker_end End marker.
275	* @param bool $automatic True when Vigilant removes the block by itself
276	* (a mode expiring on cron), false when a person
277	* asked for it. Same distinction as add_block().
278	* @return bool\|WP_Error
279	*/
280	public function remove_block( $marker_start, $marker_end, $automatic = false ) {
281	$allowed = $automatic
282	? Vigilante_Settings::owns_shared_files()
283	: Vigilante_Settings::can_write_shared_files();
284
285	if ( ! $allowed ) {
286	return new WP_Error( 'network_not_owner', Vigilante_Settings::get_shared_files_notice() );
287	}
288
289	if ( ! $this->acquire_lock() ) {
290	return new WP_Error( 'locked', __( 'Another process is writing .htaccess right now', 'vigilante' ) );
291	}
292
293	try {
294	// Read current content
295	$content = $this->read_file();
296
297	if ( false === $content \|\| empty( $content ) ) {
298	// An unreadable file proves nothing about the block, so its
299	// record stays. A missing or empty one has no block left.
300	if ( false !== $content ) {
301	$this->forget_owned_block( $marker_start );
302	}
303	return true; // Nothing to remove
304	}
305
306	// Check if block exists
307	if ( strpos( $content, $marker_start ) === false ) {
308	$this->forget_owned_block( $marker_start );
309	return true; // Block doesn't exist, nothing to do
310	}
311
312	// A block that has lost a marker would take the rest of the file with it.
313	if ( ! $this->blocks_are_whole( $content, $marker_start, $marker_end ) ) {
314	return new WP_Error( 'block_incomplete', __( 'A Vigilant block in .htaccess is missing one of its markers, so the file was left as it is.', 'vigilante' ) );
315	}
316
317	// Create backup before modification
318	$this->create_backup( $content );
319
320	// Remove the block
321	$new_content = $this->remove_block_from_content( $content, $marker_start, $marker_end );
322
323	// Validate result - WordPress rules should still be there if they were before
324	if ( strpos( $content, '# BEGIN WordPress' ) !== false &&
325	strpos( $new_content, '# BEGIN WordPress' ) === false ) {
326	// WordPress rules were removed - this is wrong, restore backup
327	$this->restore_backup();
328	return new WP_Error( 'wordpress_rules_lost', __( 'Operation would remove WordPress rules, aborted', 'vigilante' ) );
329	}
330
331	// Write file
332	if ( $this->write_file( $new_content ) ) {
333	$this->forget_owned_block( $marker_start );
334	return true;
335	}
336
337	// Write failed, restore backup
338	$this->restore_backup();
339	return new WP_Error( 'write_failed', __( 'Failed to write .htaccess', 'vigilante' ) );
340	} finally {
341	// No .htaccess content, which may hold secrets, is left in the
342	// options table after the operation. Since 2.11.9.
343	$this->clear_backup();
344	$this->release_lock();
345	}
346	}
347
348	/**
349	* Check if a block exists in .htaccess
350	*
351	* @param string $marker_start Start marker.
352	* @return bool
353	*/
354	public function block_exists( $marker_start ) {
355	$content = $this->read_file();
356	if ( false === $content ) {
357	return false;
358	}
359	return strpos( $content, $marker_start ) !== false;
360	}
361
362	/**
363	* Whether no start marker of a block is left without its end
364	*
365	* The removal below works line by line and keeps dropping lines from a start
366	* marker until it meets an end marker, so a start whose end is missing, or a
367	* second start before the end, takes everything after it. Neither existing
368	* check catches that: remove_block() only looks for "# BEGIN WordPress",
369	* which the rules Network Setup hands out do not carry, and the
370	* validate_content() of add_block() only compares marker pairs, which still
371	* match once both WordPress markers have been cut away. An end marker with
372	* no start before it is harmless to the removal, which just drops that
373	* line, so it does not count against the content.
374	*
375	* @since 2.11.6
376	*
377	* @param string $content Content to check.
378	* @param string $marker_start Start marker.
379	* @param string $marker_end End marker.
380	* @return bool
381	*/
382	private function blocks_are_whole( $content, $marker_start, $marker_end ) {
383	$inside = false;
384
385	foreach ( explode( "\n", $content ) as $line ) {
386	$line = trim( $line );
387
388	if ( $line === $marker_start ) {
389	if ( $inside ) {
390	return false;
391	}
392	$inside = true;
393	} elseif ( $line === $marker_end ) {
394	$inside = false;
395	}
396	}
397
398	return ! $inside;
399	}
400
401	/**
402	* Remove a specific block from content string
403	*
404	* @param string $content Content to modify.
405	* @param string $marker_start Start marker.
406	* @param string $marker_end End marker.
407	* @return string Modified content.
408	*/
409	private function remove_block_from_content( $content, $marker_start, $marker_end ) {
410	if ( strpos( $content, $marker_start ) === false ) {
411	return $content;
412	}
413
414	// Use line-by-line approach for safety (regex can be unpredictable)
415	$lines = explode( "\n", $content );
416	$new_lines = array();
417	$inside_block = false;
418
419	foreach ( $lines as $line ) {
420	// Check for start marker
421	if ( trim( $line ) === $marker_start ) {
422	$inside_block = true;
423	continue;
424	}
425
426	// Check for end marker
427	if ( trim( $line ) === $marker_end ) {
428	$inside_block = false;
429	continue;
430	}
431
432	// Add line if not inside our block
433	if ( ! $inside_block ) {
434	$new_lines[] = $line;
435	}
436	}
437
438	// Join and clean up multiple empty lines
439	$result = implode( "\n", $new_lines );
440	$result = preg_replace( '/\n{3,}/', "\n\n", $result );
441	$result = trim( $result );
442
443	return $result;
444	}
445
446	/**
447	* Insert a block at the specified position
448	*
449	* @param string $content Current content.
450	* @param string $block Block to insert.
451	* @param string $position Position: 'top' or 'before_wordpress'.
452	* @return string Modified content.
453	*/
454	private function insert_block( $content, $block, $position ) {
455	$content = trim( $content );
456
457	if ( empty( $content ) ) {
458	return $block . "\n";
459	}
460
461	if ( 'before_wordpress' === $position ) {
462	$pos = stripos( $content, '# BEGIN WordPress' );
463
464	/*
465	* Spliced by offset, never with preg_replace().
466	*
467	* The block used to be passed as the replacement argument, where
468	* "$1" and "\\1" are backreference syntax and a trailing backslash
469	* escapes whatever follows it. That silently ate the escaping that
470	* generate_whitelist_exceptions() had just applied: a User-Agent
471	* whitelist entry ending in a backslash reached the file as
472	* `"!Bot\\" [NC]`, the backslash escaped the closing quote, and
473	* Apache answered 500 for the whole site. Reproduced from the
474	* settings screen on 25 aug 2026. substr() copies the block
475	* verbatim, which is the only correct thing to do here.
476	*/
477	if ( false !== $pos ) {
478	return substr( $content, 0, $pos ) . $block . "\n\n" . substr( $content, $pos );
479	}
480	}
481
482	// Default: insert at top
483	return $block . "\n\n" . $content;
484	}
485
486	/**
487	* Validate .htaccess content
488	*
489	* @param string $content Content to validate.
490	* @return bool
491	*/
492	private function validate_content( $content ) {
493	// Empty content is valid (but unusual)
494	if ( empty( trim( $content ) ) ) {
495	return true;
496	}
497
498	// Check for unmatched block markers
499	foreach ( $this->known_blocks as $start => $end ) {
500	$has_start = strpos( $content, $start ) !== false;
501	$has_end = strpos( $content, $end ) !== false;
502
503	// If has start, must have end (and vice versa)
504	if ( $has_start !== $has_end ) {
505	return false;
506	}
507
508	// Start must come before end
509	if ( $has_start && $has_end ) {
510	if ( strpos( $content, $start ) > strpos( $content, $end ) ) {
511	return false;
512	}
513	}
514	}
515
516	// Basic check: if it starts with PHP code, it's wrong
517	if ( preg_match( '/^<\?php/i', trim( $content ) ) ) {
518	return false;
519	}
520
521	/*
522	* Every directive argument has to close the quotes it opens. A stray
523	* backslash right before the closing quote escapes it, the directive
524	* runs on into the rest of the line and Apache answers 500 for the
525	* whole site. That is not hypothetical: until 2.10.0 a User-Agent
526	* whitelist entry ending in a backslash did exactly that, and this
527	* function waved it through because the only syntax check it had was
528	* an unused array of patterns.
529	*
530	* Escaped pairs are removed first, so a legitimate \\" or \\\\ inside an
531	* argument is not miscounted.
532	*/
533	foreach ( preg_split( '/\r\n\|\r\|\n/', $content ) as $line ) {
534	$unescaped = str_replace( array( '\\\\', '\\"' ), '', $line );
535
536	if ( 0 !== ( substr_count( $unescaped, '"' ) % 2 ) ) {
537	return false;
538	}
539	}
540
541	/*
542	* Container tags have to balance. An unclosed <IfModule> swallows every
543	* directive below it, including the ones WordPress itself wrote.
544	*/
545	if ( preg_match_all( '/^\s<IfModule\b/im', $content ) !== preg_match_all( '/^\s<\/IfModule\s*>/im', $content ) ) {
546	return false;
547	}
548
549	return true;
550	}
551
552	/**
553	* Read .htaccess file
554	*
555	* @return string\|false
556	*/
557	private function read_file() {
558	if ( ! file_exists( $this->htaccess_path ) ) {
559	return '';
560	}
561
562	if ( ! is_readable( $this->htaccess_path ) ) {
563	return false;
564	}
565
566	$content = file_get_contents( $this->htaccess_path ); // phpcs:ignore
567
568	return ( false !== $content ) ? $content : false;
569	}
570
571	/**
572	* Write .htaccess file
573	*
574	* @param string $content Content to write.
575	* @return bool
576	*/
577	private function write_file( $content ) {
578	// Ensure content ends with newline
579	$content = rtrim( $content ) . "\n";
580
581	// Initialize WP_Filesystem
582	global $wp_filesystem;
583	if ( ! function_exists( 'WP_Filesystem' ) ) {
584	require_once ABSPATH . 'wp-admin/includes/file.php';
585	}
586	WP_Filesystem();
587
588	if ( ! $wp_filesystem ) {
589	return false;
590	}
591
592	// Check writability
593	if ( file_exists( $this->htaccess_path ) ) {
594	if ( ! $wp_filesystem->is_writable( $this->htaccess_path ) ) {
595	return false;
596	}
597	} else {
598	if ( ! $wp_filesystem->is_writable( dirname( $this->htaccess_path ) ) ) {
599	return false;
600	}
601	}
602
603	/*
604	* Keep the permissions the file already has. put_contents() always sets
605	* a mode, and FS_CHMOD_FILE is "permissions of index.php \| 0644", so
606	* until 2.11.6 every write left a .htaccess kept at 0640 at 0644 or
607	* wider. A mode that cannot be read falls back to the old one rather
608	* than to 0, which would lock the server out of the file.
609	*/
610	$perms = file_exists( $this->htaccess_path ) ? fileperms( $this->htaccess_path ) : false;
611	$mode = ( false !== $perms && ( $perms & 0777 ) ) ? ( $perms & 0777 ) : FS_CHMOD_FILE;
612
613	// Write with WP_Filesystem
614	return $wp_filesystem->put_contents( $this->htaccess_path, $content, $mode );
615	}
616
617	/**
618	* Create backup of current .htaccess, for rollback within this operation only
619	*
620	* A .htaccess can carry secrets (SetEnv credentials, an Authorization
621	* header, a php_value with a key), so this rollback buffer is a live copy of
622	* the file and is cleared at the end of every add_block/remove_block, in the
623	* finally, rather than left sitting in the options table. Until 2.11.9 it
624	* persisted between operations and a rolling five-version history kept the
625	* raw content indefinitely, so anyone who read the database or a backup of
626	* it recovered those secrets without filesystem access. Reported by the
627	* wp.org automated review of 2.11.8. The history is gone; the buffer holds
628	* the real content because restoring a redacted one would write the marker
629	* into the live file, and lives only for the length of the write.
630	*
631	* @param string $content Content to backup.
632	* @return bool
633	*/
634	private function create_backup( $content ) {
635	// A private option, never a file under the web root, and dropped again
636	// by clear_backup() in the finally of the operation that created it.
637	$stored = update_option(
638	self::BACKUP_OPTION,
639	array(
640	'content' => (string) $content,
641	'time' => time(),
642	),
643	false
644	);
645
646	// update_option() also returns false when the value is unchanged.
647	return ( false !== $stored ) \|\| ( (string) $content === $this->get_backup_content() );
648	}
649
650	/**
651	* Drop the rollback buffer, so no .htaccess content lingers in the options table
652	*
653	* @since 2.11.9
654	*/
655	private function clear_backup() {
656	delete_option( self::BACKUP_OPTION );
657	}
658
659	/**
660	* Get the stored .htaccess backup content, or '' if none.
661	*
662	* @return string
663	*/
664	private function get_backup_content() {
665	$backup = get_option( self::BACKUP_OPTION );
666	return ( is_array( $backup ) && isset( $backup['content'] ) ) ? (string) $backup['content'] : '';
667	}
668
669	/**
670	* Restore .htaccess from backup
671	*
672	* @return bool
673	*/
674	public function restore_backup() {
675	$content = $this->get_backup_content();
676
677	if ( '' === $content ) {
678	return false;
679	}
680
681	return $this->write_file( $content );
682	}
683
684	/**
685	* Check if server is Apache/LiteSpeed
686	*
687	* @return bool
688	*/
689	public function is_apache() {
690	$detected = null;
691
692	if ( function_exists( 'apache_get_modules' ) ) {
693	$detected = true;
694	} else {
695	$server = isset( $_SERVER['SERVER_SOFTWARE'] )
696	? sanitize_text_field( wp_unslash( $_SERVER['SERVER_SOFTWARE'] ) )
697	: '';
698
699	if ( '' !== $server ) {
700	$detected = self::looks_like_apache( $server );
701
702	// Remember it, because a WP-CLI run has no request to look at.
703	if ( get_option( self::SERVER_OPTION ) !== $server ) {
704	update_option( self::SERVER_OPTION, $server, false );
705	}
706	}
707	}
708
709	/*
710	* Nothing in this request to go on, which is exactly what happens under
711	* WP-CLI: apache_get_modules() only exists under mod_php and
712	* SERVER_SOFTWARE is not defined on the command line. Until 2.9.9 that
713	* answered "not Apache" and every .htaccess write was refused, so a site
714	* activated with `wp plugin activate` silently got no server layer at
715	* all while the switches showed as on. So fall back to what a web
716	* request taught us earlier.
717	*/
718	if ( null === $detected ) {
719	$remembered = (string) get_option( self::SERVER_OPTION, '' );
720
721	if ( '' !== $remembered ) {
722	$detected = self::looks_like_apache( $remembered );
723	}
724	}
725
726	/**
727	* Filter the Apache/LiteSpeed detection.
728	*
729	* The escape hatch for a site deployed entirely from the command line,
730	* where there has never been a web request to learn from.
731	*
732	* @since 2.9.9
733	*
734	* @param bool\|null $detected True, false, or null when it could not be told.
735	*/
736	$detected = apply_filters( 'vigilante_is_apache', $detected );
737
738	return ( true === $detected );
739	}
740
741	/**
742	* Vigilant blocks sitting in .htaccess files above the WordPress directory
743	*
744	* Apache applies the .htaccess of every directory above the one being
745	* served, and this class only ever writes and reads the one in ABSPATH. So
746	* a WordPress in a subfolder can be receiving rules from the block that the
747	* Vigilant of the parent installation left in the document root: the
748	* settings screen says the header is off, headers_list() does not show it,
749	* and the browser receives it all the same. Costed two rounds of diagnosis
750	* on a real site before it was understood, so it is worth naming the file.
751	*
752	* @since 2.9.9
753	*
754	* @return array<string,string[]> Absolute file path => markers found inside.
755	*/
756	public function find_blocks_above() {
757	global $wp_filesystem;
758
759	if ( ! function_exists( 'WP_Filesystem' ) ) {
760	require_once ABSPATH . 'wp-admin/includes/file.php';
761	}
762	WP_Filesystem();
763
764	if ( ! $wp_filesystem ) {
765	return array();
766	}
767
768	$found = array();
769	$markers = array_keys( $this->known_blocks );
770	$dir = dirname( $this->htaccess_path );
771
772	// Bounded walk up to the filesystem root. Eight levels is well past any
773	// real docroot and keeps this cheap on a deep path.
774	for ( $level = 0; $level < 8; $level++ ) {
775	$parent = dirname( $dir );
776
777	if ( $parent === $dir \|\| '' === $parent \|\| '.' === $parent ) {
778	break;
779	}
780
781	$dir = $parent;
782	$file = $dir . '/.htaccess';
783
784	if ( ! $wp_filesystem->exists( $file ) \|\| ! $wp_filesystem->is_readable( $file ) ) {
785	continue;
786	}
787
788	$content = $wp_filesystem->get_contents( $file );
789
790	if ( ! is_string( $content ) \|\| '' === $content ) {
791	continue;
792	}
793
794	$hits = array();
795	foreach ( $markers as $marker ) {
796	// The WordPress block is not ours, only the Vigilant ones count.
797	if ( false === strpos( $marker, 'Vigilante' ) ) {
798	continue;
799	}
800	if ( false !== strpos( $content, $marker ) ) {
801	$hits[] = $marker;
802	}
803	}
804
805	if ( ! empty( $hits ) ) {
806	$found[ $file ] = $hits;
807	}
808	}
809
810	return $found;
811	}
812
813	/**
814	* Whether a SERVER_SOFTWARE string is Apache or LiteSpeed
815	*
816	* @since 2.9.9
817	*
818	* @param string $server Server software string.
819	* @return bool
820	*/
821	private static function looks_like_apache( $server ) {
822	return ( false !== stripos( $server, 'apache' ) \|\| false !== stripos( $server, 'litespeed' ) );
823	}
824
825	/**
826	* Whether the server could not be identified in this request
827	*
828	* Tells "we know it is not Apache" apart from "we cannot tell from here",
829	* which is what a WP-CLI run gets. The caller uses it to leave the work
830	* pending for the first web request instead of dropping it.
831	*
832	* @since 2.9.9
833	*
834	* @return bool
835	*/
836	public function server_is_unknown() {
837	if ( function_exists( 'apache_get_modules' ) ) {
838	return false;
839	}
840
841	if ( ! empty( $_SERVER['SERVER_SOFTWARE'] ) ) {
842	return false;
843	}
844
845	return ( '' === (string) get_option( self::SERVER_OPTION, '' ) );
846	}
847
848	/**
849	* Check if .htaccess is writable
850	*
851	* @return bool
852	*/
853	public function is_writable() {
854	// Initialize WP_Filesystem
855	global $wp_filesystem;
856	if ( ! function_exists( 'WP_Filesystem' ) ) {
857	require_once ABSPATH . 'wp-admin/includes/file.php';
858	}
859	WP_Filesystem();
860
861	if ( ! $wp_filesystem ) {
862	return false;
863	}
864
865	if ( file_exists( $this->htaccess_path ) ) {
866	return $wp_filesystem->is_writable( $this->htaccess_path );
867	}
868	return $wp_filesystem->is_writable( ABSPATH );
869	}
870
871	/**
872	* Get current .htaccess content (for debugging)
873	*
874	* @return string
875	*/
876	public function get_content() {
877	$content = $this->read_file();
878	return ( false !== $content ) ? $content : '';
879	}
880	}