Changeset 41721 for trunk/src/wp-admin/includes/file.php

Timestamp:

10/04/2017 12:19:16 AM (7 years ago)

Author:

westonruter

Message:

File Editors: Introduce sandboxed live editing of PHP files with rollbacks for both themes and plugins.

• Edits to active plugins which cause PHP fatal errors will no longer auto-deactivate the plugin. Supersedes #39766.
• Introduce sandboxed PHP file edits for active themes, preventing accidental whitescreening of a user's site when introducing a fatal error.
• After writing a change to a PHP file for an active theme or plugin, perform loopback requests on the file editor admin screens and the homepage to check for fatal errors. If a fatal error is encountered, roll back the edited file and display the error to the user to fix and try again.
• Introduce a secure way to scrape PHP fatal errors from a site via wp_start_scraping_edited_file_errors() and wp_finalize_scraping_edited_file_errors().
• Moves file modifications from theme-editor.php and plugin-editor.php to common wp_edit_theme_plugin_file() function.
• Refactor themes and plugin editors to submit file changes via Ajax instead of doing full page refreshes when JS is available.
• Use get method for theme/plugin dropdowns.
• Improve styling of plugin editors, including width of plugin/theme dropdowns.
• Improve notices API for theme/plugin editor JS component.
• Strip common base directory from plugin file list. See #24048.
• Factor out functions to list editable file types in wp_get_theme_file_editable_extensions() and wp_get_plugin_file_editable_extensions().
• Scroll to line in editor that has linting error when attempting to save. See #41886.
• Add checkbox to dismiss lint errors to proceed with saving. See #41887.
• Only style the Update File button as disabled instead of actually disabling it for accessibility reasons.
• Ensure that value from CodeMirror is used instead of textarea when CodeMirror is present.
• Add "Are you sure?" check when leaving editor when there are unsaved changes.

Supersedes [41560].
See #39766, #24048, #41886.
Props westonruter, Clorith, melchoyce, johnbillion, jjj, jdgrimes, azaozz.
Fixes #21622, #41887.

File:

• trunk/src/wp-admin/includes/file.php (modified) (2 diffs)

trunk/src/wp-admin/includes/file.php

@@ -71 +71 @@
  *
  * @global array $wp_file_descriptions Theme file descriptions.
- * @global array $allowed_files        List of allowed files. 
+ * @global array $allowed_files        List of allowed files.
  * @param string $file Filesystem path or filename
  * @return string Description of file from $wp_file_descriptions or basename of $file if description doesn't exist.
@@ -152 +152 @@
     return $files;
 }
+
+/**
+ * Get list of file extensions that are editable in plugins.
+ *
+ * @since 4.9.0
+ *
+ * @param string $plugin Plugin.
+ * @return array File extensions.
+ */
+function wp_get_plugin_file_editable_extensions( $plugin ) {
+
+    $editable_extensions = array(
+        'bash',
+        'conf',
+        'css',
+        'diff',
+        'htm',
+        'html',
+        'http',
+        'inc',
+        'include',
+        'js',
+        'json',
+        'jsx',
+        'less',
+        'md',
+        'patch',
+        'php',
+        'php3',
+        'php4',
+        'php5',
+        'php7',
+        'phps',
+        'phtml',
+        'sass',
+        'scss',
+        'sh',
+        'sql',
+        'svg',
+        'text',
+        'txt',
+        'xml',
+        'yaml',
+        'yml',
+    );
+
+    /**
+     * Filters file type extensions editable in the plugin editor.
+     *
+     * @since 2.8.0
+     * @since 4.9.0 Adds $plugin param.
+     *
+     * @param string $plugin Plugin file.
+     * @param array $editable_extensions An array of editable plugin file extensions.
+     */
+    $editable_extensions = (array) apply_filters( 'editable_extensions', $editable_extensions, $plugin );
+
+    return $editable_extensions;
+}
+
+/**
+ * Get list of file extensions that are editable for a given theme.
+ *
+ * @param WP_Theme $theme Theme.
+ * @return array File extensions.
+ */
+function wp_get_theme_file_editable_extensions( $theme ) {
+
+    $default_types = array(
+        'bash',
+        'conf',
+        'css',
+        'diff',
+        'htm',
+        'html',
+        'http',
+        'inc',
+        'include',
+        'js',
+        'json',
+        'jsx',
+        'less',
+        'md',
+        'patch',
+        'php',
+        'php3',
+        'php4',
+        'php5',
+        'php7',
+        'phps',
+        'phtml',
+        'sass',
+        'scss',
+        'sh',
+        'sql',
+        'svg',
+        'text',
+        'txt',
+        'xml',
+        'yaml',
+        'yml',
+    );
+
+    /**
+     * Filters the list of file types allowed for editing in the Theme editor.
+     *
+     * @since 4.4.0
+     *
+     * @param array    $default_types List of file types. Default types include 'php' and 'css'.
+     * @param WP_Theme $theme         The current Theme object.
+     */
+    $file_types = apply_filters( 'wp_theme_editor_filetypes', $default_types, $theme );
+
+    // Ensure that default types are still there.
+    return array_unique( array_merge( $file_types, $default_types ) );
+}
+
+/**
+ * Print file editor templates (for plugins and themes).
+ *
+ * @since 4.9.0
+ */
+function wp_print_file_editor_templates() {
+    ?>
+    <script type="text/html" id="tmpl-wp-file-editor-notice">
+        <div class="notice inline notice-{{ data.type || 'info' }} {{ data.alt ? 'notice-alt' : '' }} {{ data.dismissible ? 'is-dismissible' : '' }} {{ data.classes || '' }}">
+            <# if ( 'php_error' === data.code ) { #>
+                <p>
+                    <?php
+                    printf(
+                        /* translators: %$1s is line number and %1$s is file path. */
+                        __( 'Your PHP code changes were rolled back due to an error on line %1$s of file %2$s. Please fix and try saving again.' ),
+                        '{{ data.line }}',
+                        '{{ data.file }}'
+                    );
+                    ?>
+                </p>
+                <pre>{{ data.message }}</pre>
+            <# } else if ( 'file_not_writable' === data.code ) { #>
+                <p><?php _e( 'You need to make this file writable before you can save your changes. See <a href="https://codex.wordpress.org/Changing_File_Permissions">the Codex</a> for more information.' ); ?></p>
+            <# } else { #>
+                <p>{{ data.message || data.code }}</p>
+
+                <# if ( 'lint_errors' === data.code ) { #>
+                    <p>
+                        <# var elementId = 'el-' + String( Math.random() ); #>
+                        <input id="{{ elementId }}"  type="checkbox">
+                        <label for="{{ elementId }}"><?php _e( 'Update anyway, even though it might break your site?' ); ?></label>
+                    </p>
+                <# } #>
+            <# } #>
+            <# if ( data.dismissible ) { #>
+                <button type="button" class="notice-dismiss"><span class="screen-reader-text"><?php _e( 'Dismiss' ); ?></span></button>
+            <# } #>
+        </div>
+    </script>
+    <?php
+}
+
+/**
+ * Attempt to edit a file for a theme or plugin.
+ *
+ * When editing a PHP file, loopback requests will be made to the admin and the homepage
+ * to attempt to see if there is a fatal error introduced. If so, the PHP change will be
+ * reverted.
+ *
+ * @since 4.9.0
+ *
+ * @param array $args {
+ *     Args. Note that all of the arg values are already unslashed. They are, however,
+ *     coming straight from $_POST and are not validated or sanitized in any way.
+ *
+ *     @type string $file       Relative path to file.
+ *     @type string $plugin     Plugin being edited.
+ *     @type string $theme      Theme being edited.
+ *     @type string $newcontent New content for the file.
+ *     @type string $nonce      Nonce.
+ * }
+ * @return true|WP_Error True on success or `WP_Error` on failure.
+ */
+function wp_edit_theme_plugin_file( $args ) {
+    if ( empty( $args['file'] ) ) {
+        return new WP_Error( 'missing_file' );
+    }
+    $file = $args['file'];
+    if ( 0 !== validate_file( $file ) ) {
+        return new WP_Error( 'bad_file' );
+    }
+
+    if ( ! isset( $args['newcontent'] ) ) {
+        return new WP_Error( 'missing_content' );
+    }
+    $content = $args['newcontent'];
+
+    if ( ! isset( $args['nonce'] ) ) {
+        return new WP_Error( 'missing_nonce' );
+    }
+
+    $plugin = null;
+    $theme = null;
+    $real_file = null;
+    if ( ! empty( $args['plugin'] ) ) {
+        $plugin = $args['plugin'];
+
+        if ( ! current_user_can( 'edit_plugins' ) ) {
+            return new WP_Error( 'unauthorized', __( 'Sorry, you are not allowed to edit plugins for this site.' ) );
+        }
+
+        if ( ! wp_verify_nonce( $args['nonce'], 'edit-plugin_' . $file ) ) {
+            return new WP_Error( 'nonce_failure' );
+        }
+
+        if ( ! array_key_exists( $plugin, get_plugins() ) ) {
+            return new WP_Error( 'invalid_plugin' );
+        }
+
+        if ( 0 !== validate_file( $file, get_plugin_files( $plugin ) ) ) {
+            return new WP_Error( 'bad_plugin_file_path', __( 'Sorry, that file cannot be edited.' ) );
+        }
+
+        $editable_extensions = wp_get_plugin_file_editable_extensions( $plugin );
+
+        $real_file = WP_PLUGIN_DIR . '/' . $file;
+
+        $is_active = in_array(
+            $plugin,
+            (array) get_option( 'active_plugins', array() ),
+            true
+        );
+
+    } elseif ( ! empty( $args['theme'] ) ) {
+        $stylesheet = $args['theme'];
+        if ( 0 !== validate_file( $stylesheet ) ) {
+            return new WP_Error( 'bad_theme_path' );
+        }
+
+        if ( ! current_user_can( 'edit_themes' ) ) {
+            return new WP_Error( 'unauthorized', __( 'Sorry, you are not allowed to edit templates for this site.' ) );
+        }
+
+        $theme = wp_get_theme( $stylesheet );
+        if ( ! $theme->exists() ) {
+            return new WP_Error( 'non_existent_theme', __( 'The requested theme does not exist.' ) );
+        }
+
+        $real_file = $theme->get_stylesheet_directory() . '/' . $file;
+        if ( ! wp_verify_nonce( $args['nonce'], 'edit-theme_' . $real_file . $stylesheet ) ) {
+            return new WP_Error( 'nonce_failure' );
+        }
+
+        if ( $theme->errors() && 'theme_no_stylesheet' === $theme->errors()->get_error_code() ) {
+            return new WP_Error(
+                'theme_no_stylesheet',
+                __( 'The requested theme does not exist.' ) . ' ' . $theme->errors()->get_error_message()
+            );
+        }
+
+        $editable_extensions = wp_get_theme_file_editable_extensions( $theme );
+
+        $allowed_files = array();
+        foreach ( $editable_extensions as $type ) {
+            switch ( $type ) {
+                case 'php':
+                    $allowed_files = array_merge( $allowed_files, $theme->get_files( 'php', 1 ) );
+                    break;
+                case 'css':
+                    $style_files = $theme->get_files( 'css' );
+                    $allowed_files['style.css'] = $style_files['style.css'];
+                    $allowed_files = array_merge( $allowed_files, $style_files );
+                    break;
+                default:
+                    $allowed_files = array_merge( $allowed_files, $theme->get_files( $type ) );
+                    break;
+            }
+        }
+
+        if ( 0 !== validate_file( $real_file, $allowed_files ) ) {
+            return new WP_Error( 'disallowed_theme_file', __( 'Sorry, that file cannot be edited.' ) );
+        }
+
+        $is_active = ( get_stylesheet() === $stylesheet || get_template() === $stylesheet );
+    } else {
+        return new WP_Error( 'missing_theme_or_plugin' );
+    }
+
+    // Ensure file is real.
+    if ( ! is_file( $real_file ) ) {
+        return new WP_Error( 'file_does_not_exist', __( 'No such file exists! Double check the name and try again.' ) );
+    }
+
+    // Ensure file extension is allowed.
+    $extension = null;
+    if ( preg_match( '/\.([^.]+)$/', $real_file, $matches ) ) {
+        $extension = strtolower( $matches[1] );
+        if ( ! in_array( $extension, $editable_extensions, true ) ) {
+            return new WP_Error( 'illegal_file_type', __( 'Files of this type are not editable.' ) );
+        }
+    }
+
+    $previous_content = file_get_contents( $real_file );
+
+    if ( ! is_writeable( $real_file ) ) {
+        return new WP_Error( 'file_not_writable' );
+    }
+
+    $f = fopen( $real_file, 'w+' );
+    if ( false === $f ) {
+        return new WP_Error( 'file_not_writable' );
+    }
+
+    $written = fwrite( $f, $content );
+    fclose( $f );
+    if ( false === $written ) {
+        return new WP_Error( 'unable_to_write', __( 'Unable to write to file.' ) );
+    }
+    if ( 'php' === $extension && function_exists( 'opcache_invalidate' ) ) {
+        opcache_invalidate( $real_file, true );
+    }
+
+    if ( $is_active && 'php' === $extension ) {
+
+        $scrape_key = md5( rand() );
+        $transient = 'scrape_key_' . $scrape_key;
+        $scrape_nonce = strval( rand() );
+        set_transient( $transient, $scrape_nonce, 60 ); // It shouldn't take more than 60 seconds to make the two loopback requests.
+
+        $cookies = wp_unslash( $_COOKIE );
+        $scrape_params = array(
+            'wp_scrape_key' => $scrape_key,
+            'wp_scrape_nonce' => $scrape_nonce,
+        );
+        $headers = array(
+            'Cache-Control' => 'no-cache',
+        );
+
+        $needle = "###### begin_scraped_error:$scrape_key ######";
+
+        // Attempt loopback request to editor to see if user just whitescreened themselves.
+        if ( $plugin ) {
+            $url = add_query_arg( compact( 'plugin', 'file' ), admin_url( 'plugin-editor.php' ) );
+        } elseif ( isset( $stylesheet ) ) {
+            $url = add_query_arg(
+                array(
+                    'theme' => $stylesheet,
+                    'file' => $file,
+                ),
+                admin_url( 'theme-editor.php' )
+            );
+        } else {
+            $url = admin_url();
+        }
+        $url = add_query_arg( $scrape_params, $url );
+        $r = wp_remote_get( $url, compact( 'cookies', 'headers' ) );
+        $body = wp_remote_retrieve_body( $r );
+        $error_position = strpos( $body, $needle );
+
+        // Try making request to homepage as well to see if visitors have been whitescreened.
+        if ( false === $error_position ) {
+            $url = home_url( '/' );
+            $url = add_query_arg( $scrape_params, $url );
+            $r = wp_remote_get( $url, compact( 'cookies', 'headers' ) );
+            $body = wp_remote_retrieve_body( $r );
+            $error_position = strpos( $body, $needle );
+        }
+
+        delete_transient( $transient );
+
+        if ( false !== $error_position ) {
+            file_put_contents( $real_file, $previous_content );
+            if ( function_exists( 'opcache_invalidate' ) ) {
+                opcache_invalidate( $real_file, true );
+            }
+
+            $error_output = trim( substr( $body, $error_position + strlen( $needle ) ) );
+            $error = json_decode( $error_output, true );
+            if ( ! isset( $error['message'] ) ) {
+                $message = $error_output;
+            } else {
+                $message = $error['message'];
+                unset( $error['message'] );
+            }
+            return new WP_Error( 'php_error', $message, $error );
+        }
+    }
+
+    if ( $theme instanceof WP_Theme ) {
+        $theme->cache_delete();
+    }
+
+    return true;
+}
+
 
 /**