← All changes | includes/mcp/class-mcp-static-discovery.php +144 -2 2.0.0 → 2.9.0 View file →

		@@ -24,8 +24,19 @@
24	24	* and no files are written, so metadata can never go stale there);
25	25	* - content is refreshed on every publish, so each self-test run keeps the
26	26	* files current with home_url()/settings changes.
27	27	*
	28	+ * The documents embed absolute, home_url()-derived identifiers (issuer,
	29	+ * resource, authorization_endpoint, token_endpoint), and the whole point of
	30	+ * writing them as files is that the web server serves them BEFORE WordPress.
	31	+ * So once the site's URL changes, the stale copy wins over the correct dynamic
	32	+ * route and the site advertises its previous domain's issuer — which a
	33	+ * spec-compliant client is required to reject. Nothing used to rewrite them:
	34	+ * publish() ran only from the self-test and remove() only on deactivation, so
	35	+ * the files sat there advertising a domain the site no longer has, with no
	36	+ * signal anywhere (#486). refresh(), hooked to both URL options, is what keeps
	37	+ * them honest.
	38	+ *
28	39	* Known limitation: the files are extensionless (the URL path has no .json),
29	40	* so an edge server may send them without an application/json Content-Type.
30	41	* Every client observed so far parses the body regardless, and a 200 with a
31	42	* loose Content-Type strictly beats the 404 it replaces.
		@@ -64,8 +75,133 @@
64	75	];
65	76	}
66	77
67	78	/**
	79	+ * Hook the site-URL options so published files cannot outlive the URL they
	80	+ * were generated for.
	81	+ *
	82	+ * Registered unconditionally, not behind `enable_mcp`: a stale document is
	83	+ * harmful whether or not the MCP server is currently switched on, and
	84	+ * these files are served without WordPress having any say in it.
	85	+ *
	86	+ * @since 2.1.0
	87	+ *
	88	+ * @return void
	89	+ */
	90	+ public static function init(): void {
	91	+ // accepted_args = 0 on purpose. update_option_{$option} fires with
	92	+ // ( $old_value, $value, $option ), and refresh()'s only parameter is a
	93	+ // base DIRECTORY — so the default of 1 would hand it the previous site
	94	+ // URL as a filesystem path and it would silently find nothing to do.
	95	+ add_action( 'update_option_home', [ __CLASS__, 'refresh' ], 10, 0 );
	96	+ add_action( 'update_option_siteurl', [ __CLASS__, 'refresh' ], 10, 0 );
	97	+ }
	98	+
	99	+ /**
	100	+ * Bring published files back in line with the current site URL.
	101	+ *
	102	+ * Deliberately does NOT publish where nothing was published before —
	103	+ * writing these files is the self-test's call, made only after it has
	104	+ * measured that the dynamic route is dead. This just keeps an existing
	105	+ * set honest.
	106	+ *
	107	+ * If a rewrite is not possible (permissions changed with the move, which
	108	+ * is common), the files are removed instead. No document beats a document
	109	+ * naming the wrong issuer: without the files the dynamic route serves
	110	+ * again, and the next self-test run republishes if it is still needed.
	111	+ *
	112	+ * @since 2.1.0
	113	+ *
	114	+ * @param string|null $base Base directory (defaults to ABSPATH); a
	115	+ * parameter so tests can point it at a sandbox.
	116	+ * @return void
	117	+ */
	118	+ public static function refresh( ?string $base = null ): void {
	119	+ if ( ! self::published( $base ) ) {
	120	+ return;
	121	+ }
	122	+
	123	+ if ( ! self::publish( $base ) ) {
	124	+ self::remove( $base );
	125	+ }
	126	+ }
	127	+
	128	+ /**
	129	+ * Whether any of the discovery documents exist on disk.
	130	+ *
	131	+ * @since 2.1.0
	132	+ *
	133	+ * @param string|null $base Base directory (defaults to ABSPATH).
	134	+ * @return bool
	135	+ */
	136	+ public static function published( ?string $base = null ): bool {
	137	+ $base = trailingslashit( $base ?? ABSPATH );
	138	+
	139	+ foreach ( array_keys( self::files() ) as $relative ) {
	140	+ if ( is_file( $base . $relative ) ) {
	141	+ return true;
	142	+ }
	143	+ }
	144	+
	145	+ return false;
	146	+ }
	147	+
	148	+ /**
	149	+ * The identifier a published file advertises, when it disagrees with what
	150	+ * this site is now.
	151	+ *
	152	+ * Read off disk rather than over HTTP on purpose. The HTTP probe only sees
	153	+ * these files on a host that actually serves /.well-known/ ahead of
	154	+ * WordPress, and loopback does not always take the same path an external
	155	+ * client does — so a site can serve a stale document to the whole internet
	156	+ * while the self-test's own request never sees it.
	157	+ *
	158	+ * @since 2.1.0
	159	+ *
	160	+ * @param string|null $base Base directory (defaults to ABSPATH).
	161	+ * @return array{file:string,key:string,found:string,expected:string}|null
	162	+ */
	163	+ public static function stale_document( ?string $base = null ): ?array {
	164	+ $base = trailingslashit( $base ?? ABSPATH );
	165	+
	166	+ $identifiers = [
	167	+ '.well-known/oauth-protected-resource/' . Mcp_Pairing::SITE_ENDPOINT_PATH => [
	168	+ 'key' => 'resource',
	169	+ 'expected' => Mcp_Pairing::site_endpoint(),
	170	+ ],
	171	+ '.well-known/oauth-authorization-server/' . Mcp_Pairing::SITE_ENDPOINT_PATH => [
	172	+ 'key' => 'issuer',
	173	+ 'expected' => Mcp_OAuth::issuer(),
	174	+ ],
	175	+ ];
	176	+
	177	+ foreach ( $identifiers as $relative => $spec ) {
	178	+ $path = $base . $relative;
	179	+
	180	+ if ( ! is_file( $path ) ) {
	181	+ continue;
	182	+ }
	183	+
	184	+ // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents -- local file we wrote ourselves.
	185	+ $document = json_decode( (string) file_get_contents( $path ), true );
	186	+ $found = is_array( $document ) && isset( $document[ $spec['key'] ] )
	187	+ ? (string) $document[ $spec['key'] ]
	188	+ : '';
	189	+
	190	+ if ( $found !== $spec['expected'] ) {
	191	+ return [
	192	+ 'file' => $relative,
	193	+ 'key' => $spec['key'],
	194	+ 'found' => $found,
	195	+ 'expected' => $spec['expected'],
	196	+ ];
	197	+ }
	198	+ }
	199	+
	200	+ return null;
	201	+ }
	202	+
	203	+ /**
68	204	* Whether static publishing is even applicable here.
69	205	*
70	206	* @return bool
71	207	*/
		@@ -102,10 +238,16 @@
102	238	if ( ! wp_mkdir_p( dirname( $path ) ) ) {
103	239	$all_current = false;
104	240	continue;
105	241	}
106		- // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_file_put_contents -- small static file at a fixed path; WP_Filesystem adds credential prompts this non-interactive path cannot answer.
107		- if ( false === file_put_contents( $path, $json ) ) {
	242	+ // Silenced deliberately: failing to write here is an ANTICIPATED
	243	+ // outcome, handled by the return value — the site root is often
	244	+ // not writable, and after a migration the files can be owned by
	245	+ // someone else (#486). A raw PHP warning would be emitted into
	246	+ // whatever response happens to be open, which for the self-test
	247	+ // means corrupting its JSON body.
	248	+ // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_file_put_contents, WordPress.PHP.NoSilencedErrors.Discouraged -- small static file at a fixed path; WP_Filesystem adds credential prompts this non-interactive path cannot answer.
	249	+ if ( false === @file_put_contents( $path, $json ) ) {
108	250	$all_current = false;
109	251	}
110	252	}
111	253