* * This function only accepts valid named entity references, which are finite, * case-sensitive, and highly scrutinized by HTML and XML validators. * * @since 3.0.0 * * @global array $allowedentitynames * * @param array $matches preg_replace_callback() matches array. * @return string Correctly encoded entity. */ function wp_kses_named_entities( $matches ) { global $allowedentitynames; if ( empty( $matches[1] ) ) { return ''; } $i = $matches[1]; return ( ! in_array( $i, $allowedentitynames, true ) ) ? "&$i;" : "&$i;"; } /** * Callback for `wp_kses_normalize_entities()` regular expression. * * This function only accepts valid named entity references, which are finite, * case-sensitive, and highly scrutinized by XML validators. HTML named entity * references are converted to their code points. * * @since 5.5.0 * * @global array $allowedentitynames * @global array $allowedxmlentitynames * * @param array $matches preg_replace_callback() matches array. * @return string Correctly encoded entity. */ function wp_kses_xml_named_entities( $matches ) { global $allowedentitynames, $allowedxmlentitynames; if ( empty( $matches[1] ) ) { return ''; } $i = $matches[1]; if ( in_array( $i, $allowedxmlentitynames, true ) ) { return "&$i;"; } elseif ( in_array( $i, $allowedentitynames, true ) ) { return html_entity_decode( "&$i;", ENT_HTML5 ); } return "&$i;"; } /** * Callback for `wp_kses_normalize_entities()` regular expression. * * This function helps `wp_kses_normalize_entities()` to only accept 16-bit * values and nothing more for `&#number;` entities. * * @access private * @ignore * @since 1.0.0 * * @param array $matches `preg_replace_callback()` matches array. * @return string Correctly encoded entity. */ function wp_kses_normalize_entities2( $matches ) { if ( empty( $matches[1] ) ) { return ''; } $i = $matches[1]; if ( valid_unicode( $i ) ) { $i = str_pad( ltrim( $i, '0' ), 3, '0', STR_PAD_LEFT ); $i = "&#$i;"; } else { $i = "&#$i;"; } return $i; } /** * Callback for `wp_kses_normalize_entities()` for regular expression. * * This function helps `wp_kses_normalize_entities()` to only accept valid Unicode * numeric entities in hex form. * * @since 2.7.0 * @access private * @ignore * * @param array $matches `preg_replace_callback()` matches array. * @return string Correctly encoded entity. */ function wp_kses_normalize_entities3( $matches ) { if ( empty( $matches[1] ) ) { return ''; } $hexchars = $matches[1]; return ( ! valid_unicode( hexdec( $hexchars ) ) ) ? "&#x$hexchars;" : '&#x' . ltrim( $hexchars, '0' ) . ';'; } /** * Determines if a Unicode codepoint is valid. * * @since 2.7.0 * * @param int $i Unicode codepoint. * @return bool Whether or not the codepoint is a valid Unicode codepoint. */ function valid_unicode( $i ) { return ( 0x9 == $i || 0xa == $i || 0xd == $i || ( 0x20 <= $i && $i <= 0xd7ff ) || ( 0xe000 <= $i && $i <= 0xfffd ) || ( 0x10000 <= $i && $i <= 0x10ffff ) ); } /** * Converts all numeric HTML entities to their named counterparts. * * This function decodes numeric HTML entities (`A` and `A`). * It doesn't do anything with named entities like `ä`, but we don't * need them in the allowed URL protocols system anyway. * * @since 1.0.0 * * @param string $string Content to change entities. * @return string Content after decoded entities. */ function wp_kses_decode_entities( $string ) { $string = preg_replace_callback( '/&#([0-9]+);/', '_wp_kses_decode_entities_chr', $string ); $string = preg_replace_callback( '/&#[Xx]([0-9A-Fa-f]+);/', '_wp_kses_decode_entities_chr_hexdec', $string ); return $string; } /** * Regex callback for `wp_kses_decode_entities()`. * * @since 2.9.0 * @access private * @ignore * * @param array $match preg match * @return string */ function _wp_kses_decode_entities_chr( $match ) { return chr( $match[1] ); } /** * Regex callback for `wp_kses_decode_entities()`. * * @since 2.9.0 * @access private * @ignore * * @param array $match preg match * @return string */ function _wp_kses_decode_entities_chr_hexdec( $match ) { return chr( hexdec( $match[1] ) ); } /** * Sanitize content with allowed HTML KSES rules. * * This function expects slashed data. * * @since 1.0.0 * * @param string $data Content to filter, expected to be escaped with slashes. * @return string Filtered content. */ function wp_filter_kses( $data ) { return addslashes( wp_kses( stripslashes( $data ), current_filter() ) ); } /** * Sanitize content with allowed HTML KSES rules. * * This function expects unslashed data. * * @since 2.9.0 * * @param string $data Content to filter, expected to not be escaped. * @return string Filtered content. */ function wp_kses_data( $data ) { return wp_kses( $data, current_filter() ); } /** * Sanitizes content for allowed HTML tags for post content. * * Post content refers to the page contents of the 'post' type and not `$_POST` * data from forms. * * This function expects slashed data. * * @since 2.0.0 * * @param string $data Post content to filter, expected to be escaped with slashes. * @return string Filtered post content with allowed HTML tags and attributes intact. */ function wp_filter_post_kses( $data ) { return addslashes( wp_kses( stripslashes( $data ), 'post' ) ); } /** * Sanitizes global styles user content removing unsafe rules. * * @since 5.9.0 * * @param string $data Post content to filter. * @return string Filtered post content with unsafe rules removed. */ function wp_filter_global_styles_post( $data ) { $decoded_data = json_decode( wp_unslash( $data ), true ); $json_decoding_error = json_last_error(); if ( JSON_ERROR_NONE === $json_decoding_error && is_array( $decoded_data ) && isset( $decoded_data['isGlobalStylesUserThemeJSON'] ) && $decoded_data['isGlobalStylesUserThemeJSON'] ) { unset( $decoded_data['isGlobalStylesUserThemeJSON'] ); $data_to_encode = WP_Theme_JSON::remove_insecure_properties( $decoded_data ); $data_to_encode['isGlobalStylesUserThemeJSON'] = true; return wp_slash( wp_json_encode( $data_to_encode ) ); } return $data; } /** * Sanitizes content for allowed HTML tags for post content. * * Post content refers to the page contents of the 'post' type and not `$_POST` * data from forms. * * This function expects unslashed data. * * @since 2.9.0 * * @param string $data Post content to filter. * @return string Filtered post content with allowed HTML tags and attributes intact. */ function wp_kses_post( $data ) { return wp_kses( $data, 'post' ); } /** * Navigates through an array, object, or scalar, and sanitizes content for * allowed HTML tags for post content. * * @since 4.4.2 * * @see map_deep() * * @param mixed $data The array, object, or scalar value to inspect. * @return mixed The filtered content. */ function wp_kses_post_deep( $data ) { return map_deep( $data, 'wp_kses_post' ); } /** * Strips all HTML from a text string. * * This function expects slashed data. * * @since 2.1.0 * * @param string $data Content to strip all HTML from. * @return string Filtered content without any HTML. */ function wp_filter_nohtml_kses( $data ) { return addslashes( wp_kses( stripslashes( $data ), 'strip' ) ); } /** * Adds all KSES input form content filters. * * All hooks have default priority. The `wp_filter_kses()` function is added to * the 'pre_comment_content' and 'title_save_pre' hooks. * * The `wp_filter_post_kses()` function is added to the 'content_save_pre', * 'excerpt_save_pre', and 'content_filtered_save_pre' hooks. * * @since 2.0.0 */ function kses_init_filters() { // Normal filtering. add_filter( 'title_save_pre', 'wp_filter_kses' ); // Comment filtering. if ( current_user_can( 'unfiltered_html' ) ) { add_filter( 'pre_comment_content', 'wp_filter_post_kses' ); } else { add_filter( 'pre_comment_content', 'wp_filter_kses' ); } // Global Styles filtering: Global Styles filters should be executed before normal post_kses HTML filters. add_filter( 'content_save_pre', 'wp_filter_global_styles_post', 9 ); add_filter( 'content_filtered_save_pre', 'wp_filter_global_styles_post', 9 ); // Post filtering. add_filter( 'content_save_pre', 'wp_filter_post_kses' ); add_filter( 'excerpt_save_pre', 'wp_filter_post_kses' ); add_filter( 'content_filtered_save_pre', 'wp_filter_post_kses' ); } /** * Removes all KSES input form content filters. * * A quick procedural method to removing all of the filters that KSES uses for * content in WordPress Loop. * * Does not remove the `kses_init()` function from {@see 'init'} hook (priority is * default). Also does not remove `kses_init()` function from {@see 'set_current_user'} * hook (priority is also default). * * @since 2.0.6 */ function kses_remove_filters() { // Normal filtering. remove_filter( 'title_save_pre', 'wp_filter_kses' ); // Comment filtering. remove_filter( 'pre_comment_content', 'wp_filter_post_kses' ); remove_filter( 'pre_comment_content', 'wp_filter_kses' ); // Global Styles filtering. remove_filter( 'content_save_pre', 'wp_filter_global_styles_post', 9 ); remove_filter( 'content_filtered_save_pre', 'wp_filter_global_styles_post', 9 ); // Post filtering. remove_filter( 'content_save_pre', 'wp_filter_post_kses' ); remove_filter( 'excerpt_save_pre', 'wp_filter_post_kses' ); remove_filter( 'content_filtered_save_pre', 'wp_filter_post_kses' ); } /** * Sets up most of the KSES filters for input form content. * * First removes all of the KSES filters in case the current user does not need * to have KSES filter the content. If the user does not have `unfiltered_html` * capability, then KSES filters are added. * * @since 2.0.0 */ function kses_init() { kses_remove_filters(); if ( ! current_user_can( 'unfiltered_html' ) ) { kses_init_filters(); } } /** * Filters an inline style attribute and removes disallowed rules. * * @since 2.8.1 * @since 4.4.0 Added support for `min-height`, `max-height`, `min-width`, and `max-width`. * @since 4.6.0 Added support for `list-style-type`. * @since 5.0.0 Added support for `background-image`. * @since 5.1.0 Added support for `text-transform`. * @since 5.2.0 Added support for `background-position` and `grid-template-columns`. * @since 5.3.0 Added support for `grid`, `flex` and `column` layout properties. * Extend `background-*` support of individual properties. * @since 5.3.1 Added support for gradient backgrounds. * @since 5.7.1 Added support for `object-position`. * @since 5.8.0 Added support for `calc()` and `var()` values. * * @param string $css A string of CSS rules. * @param string $deprecated Not used. * @return string Filtered string of CSS rules. */ function safecss_filter_attr( $css, $deprecated = '' ) { if ( ! empty( $deprecated ) ) { _deprecated_argument( __FUNCTION__, '2.8.1' ); // Never implemented. } $css = wp_kses_no_null( $css ); $css = str_replace( array( "\n", "\r", "\t" ), '', $css ); $allowed_protocols = wp_allowed_protocols(); $css_array = explode( ';', trim( $css ) ); /** * Filters the list of allowed CSS attributes. * * @since 2.8.1 * * @param string[] $attr Array of allowed CSS attributes. */ $allowed_attr = apply_filters( 'safe_style_css', array( 'background', 'background-color', 'background-image', 'background-position', 'background-size', 'background-attachment', 'background-blend-mode', 'border', 'border-radius', 'border-width', 'border-color', 'border-style', 'border-right', 'border-right-color', 'border-right-style', 'border-right-width', 'border-bottom', 'border-bottom-color', 'border-bottom-left-radius', 'border-bottom-right-radius', 'border-bottom-style', 'border-bottom-width', 'border-bottom-right-radius', 'border-bottom-left-radius', 'border-left', 'border-left-color', 'border-left-style', 'border-left-width', 'border-top', 'border-top-color', 'border-top-left-radius', 'border-top-right-radius', 'border-top-style', 'border-top-width', 'border-top-left-radius', 'border-top-right-radius', 'border-spacing', 'border-collapse', 'caption-side', 'columns', 'column-count', 'column-fill', 'column-gap', 'column-rule', 'column-span', 'column-width', 'color', 'filter', 'font', 'font-family', 'font-size', 'font-style', 'font-variant', 'font-weight', 'letter-spacing', 'line-height', 'text-align', 'text-decoration', 'text-indent', 'text-transform', 'height', 'min-height', 'max-height', 'width', 'min-width', 'max-width', 'margin', 'margin-right', 'margin-bottom', 'margin-left', 'margin-top', 'padding', 'padding-right', 'padding-bottom', 'padding-left', 'padding-top', 'flex', 'flex-basis', 'flex-direction', 'flex-flow', 'flex-grow', 'flex-shrink', 'grid-template-columns', 'grid-auto-columns', 'grid-column-start', 'grid-column-end', 'grid-column-gap', 'grid-template-rows', 'grid-auto-rows', 'grid-row-start', 'grid-row-end', 'grid-row-gap', 'grid-gap', 'justify-content', 'justify-items', 'justify-self', 'align-content', 'align-items', 'align-self', 'clear', 'cursor', 'direction', 'float', 'list-style-type', 'object-position', 'overflow', 'vertical-align', ) ); /* * CSS attributes that accept URL data types. * * This is in accordance to the CSS spec and unrelated to * the sub-set of supported attributes above. * * See: https://developer.mozilla.org/en-US/docs/Web/CSS/url */ $css_url_data_types = array( 'background', 'background-image', 'cursor', 'list-style', 'list-style-image', ); /* * CSS attributes that accept gradient data types. * */ $css_gradient_data_types = array( 'background', 'background-image', ); if ( empty( $allowed_attr ) ) { return $css; } $css = ''; foreach ( $css_array as $css_item ) { if ( '' === $css_item ) { continue; } $css_item = trim( $css_item ); $css_test_string = $css_item; $found = false; $url_attr = false; $gradient_attr = false; if ( strpos( $css_item, ':' ) === false ) { $found = true; } else { $parts = explode( ':', $css_item, 2 ); $css_selector = trim( $parts[0] ); if ( in_array( $css_selector, $allowed_attr, true ) ) { $found = true; $url_attr = in_array( $css_selector, $css_url_data_types, true ); $gradient_attr = in_array( $css_selector, $css_gradient_data_types, true ); } } if ( $found && $url_attr ) { // Simplified: matches the sequence `url(*)`. preg_match_all( '/url\([^)]+\)/', $parts[1], $url_matches ); foreach ( $url_matches[0] as $url_match ) { // Clean up the URL from each of the matches above. preg_match( '/^url\(\s*([\'\"]?)(.*)(\g1)\s*\)$/', $url_match, $url_pieces ); if ( empty( $url_pieces[2] ) ) { $found = false; break; } $url = trim( $url_pieces[2] ); if ( empty( $url ) || wp_kses_bad_protocol( $url, $allowed_protocols ) !== $url ) { $found = false; break; } else { // Remove the whole `url(*)` bit that was matched above from the CSS. $css_test_string = str_replace( $url_match, '', $css_test_string ); } } } if ( $found && $gradient_attr ) { $css_value = trim( $parts[1] ); if ( preg_match( '/^(repeating-)?(linear|radial|conic)-gradient\(([^()]|rgb[a]?\([^()]*\))*\)$/', $css_value ) ) { // Remove the whole `gradient` bit that was matched above from the CSS. $css_test_string = str_replace( $css_value, '', $css_test_string ); } } if ( $found ) { // Allow CSS calc(). $css_test_string = preg_replace( '/calc\(((?:\([^()]*\)?|[^()])*)\)/', '', $css_test_string ); // Allow CSS var(). $css_test_string = preg_replace( '/\(?var\(--[a-zA-Z0-9_-]*\)/', '', $css_test_string ); // Check for any CSS containing \ ( & } = or comments, // except for url(), calc(), or var() usage checked above. $allow_css = ! preg_match( '%[\\\(&=}]|/\*%', $css_test_string ); /** * Filters the check for unsafe CSS in `safecss_filter_attr`. * * Enables developers to determine whether a section of CSS should be allowed or discarded. * By default, the value will be false if the part contains \ ( & } = or comments. * Return true to allow the CSS part to be included in the output. * * @since 5.5.0 * * @param bool $allow_css Whether the CSS in the test string is considered safe. * @param string $css_test_string The CSS string to test. */ $allow_css = apply_filters( 'safecss_filter_attr_allow_css', $allow_css, $css_test_string ); // Only add the CSS part if it passes the regex check. if ( $allow_css ) { if ( '' !== $css ) { $css .= ';'; } $css .= $css_item; } } } return $css; } /** * Helper function to add global attributes to a tag in the allowed HTML list. * * @since 3.5.0 * @since 5.0.0 Added support for `data-*` wildcard attributes. * @since 6.0.0 Added `dir`, `lang`, and `xml:lang` to global attributes. * * @access private * @ignore * * @param array $value An array of attributes. * @return array The array of attributes with global attributes added. */ function _wp_add_global_attributes( $value ) { $global_attributes = array( 'aria-describedby' => true, 'aria-details' => true, 'aria-label' => true, 'aria-labelledby' => true, 'aria-hidden' => true, 'class' => true, 'data-*' => true, 'dir' => true, 'id' => true, 'lang' => true, 'style' => true, 'title' => true, 'role' => true, 'xml:lang' => true, ); if ( true === $value ) { $value = array(); } if ( is_array( $value ) ) { return array_merge( $value, $global_attributes ); } return $value; } /** * Helper function to check if this is a safe PDF URL. * * @since 5.9.0 * @access private * @ignore * * @param string $url The URL to check. * @return bool True if the URL is safe, false otherwise. */ function _wp_kses_allow_pdf_objects( $url ) { // We're not interested in URLs that contain query strings or fragments. if ( str_contains( $url, '?' ) || str_contains( $url, '#' ) ) { return false; } // If it doesn't have a PDF extension, it's not safe. if ( ! str_ends_with( $url, '.pdf' ) ) { return false; } // If the URL host matches the current site's media URL, it's safe. $upload_info = wp_upload_dir( null, false ); $parsed_url = wp_parse_url( $upload_info['url'] ); $upload_host = isset( $parsed_url['host'] ) ? $parsed_url['host'] : ''; $upload_port = isset( $parsed_url['port'] ) ? ':' . $parsed_url['port'] : ''; if ( str_starts_with( $url, "http://$upload_host$upload_port/" ) || str_starts_with( $url, "https://$upload_host$upload_port/" ) ) { return true; } return false; }