Make WordPress Core

Changeset 53584


Ignore:
Timestamp:
06/28/2022 11:25:21 AM (11 months ago)
Author:
SergeyBiryukov
Message:

Docs: Adjust some DocBlocks in wpdb per the documentation standards.

Includes:

  • Wrapping long single-line comments to multi-line for better readability.
  • Formatting code blocks to display correctly on the Code Reference.
  • Other minor edits for consistency.

This applies to:

  • wpdb::$allow_unsafe_unquoted_parameters
  • wpdb::escape_identifier()
  • wpdb::_escape_identifier_value()
  • wpdb::prepare()
  • wpdb::has_cap()

Follow-up to [53575].

See #52506, #55646.

File:
1 edited

Legend:

Unmodified
Added
Removed
  • trunk/src/wp-includes/wp-db.php

    r53575 r53584  
    646646
    647647    /**
    648      * Backwards compatibility, where wpdb::prepare() has not quoted formatted/argnum placeholders.
     648     * Backward compatibility, where wpdb::prepare() has not quoted formatted/argnum placeholders.
    649649     *
    650650     * Historically this could be used for table/field names, or for some string formatting, e.g.
    651      *   $wpdb->prepare( 'WHERE `%1s` = "%1s something %1s" OR %1$s = "%-10s"', 'field_1', 'a', 'b', 'c' );
     651     *
     652     *     $wpdb->prepare( 'WHERE `%1s` = "%1s something %1s" OR %1$s = "%-10s"', 'field_1', 'a', 'b', 'c' );
    652653     *
    653654     * But it's risky, e.g. forgetting to add quotes, resulting in SQL Injection vulnerabilities:
    654      *   $wpdb->prepare( 'WHERE (id = %1s) OR (id = %2$s)', $_GET['id'], $_GET['id'] ); // ?id=id
     655     *
     656     *     $wpdb->prepare( 'WHERE (id = %1s) OR (id = %2$s)', $_GET['id'], $_GET['id'] ); // ?id=id
    655657     *
    656658     * This feature is preserved while plugin authors update their code to use safer approaches:
    657      *   $wpdb->prepare( 'WHERE %1s = %s', $_GET['key'], $_GET['value'] );
    658      *   $wpdb->prepare( 'WHERE %i  = %s', $_GET['key'], $_GET['value'] );
     659     *
     660     *     $wpdb->prepare( 'WHERE %1s = %s', $_GET['key'], $_GET['value'] );
     661     *     $wpdb->prepare( 'WHERE %i  = %s', $_GET['key'], $_GET['value'] );
    659662     *
    660663     * While changing to false will be fine for queries not using formatted/argnum placeholders,
    661664     * any remaining cases are most likely going to result in SQL errors (good, in a way):
    662      *   $wpdb->prepare( 'WHERE %1s = "%-10s"', 'my_field', 'my_value' );
     665     *
     666     *     $wpdb->prepare( 'WHERE %1s = "%-10s"', 'my_field', 'my_value' );
    663667     *     true  = WHERE my_field = "my_value  "
    664668     *     false = WHERE 'my_field' = "'my_value  '"
     669     *
    665670     * But there may be some queries that result in an SQL Injection vulnerability:
    666      *   $wpdb->prepare( 'WHERE id = %1s', $_GET['id'] ); // ?id=id
    667      * So there may need to be a `_doing_it_wrong()` phase, after we know everyone can use Identifier
    668      * placeholders (%i), but before this feature is disabled or removed.
     671     *
     672     *     $wpdb->prepare( 'WHERE id = %1s', $_GET['id'] ); // ?id=id
     673     *
     674     * So there may need to be a `_doing_it_wrong()` phase, after we know everyone can use
     675     * identifier placeholders (%i), but before this feature is disabled or removed.
    669676     *
    670677     * @since 6.1.0
     
    13771384
    13781385    /**
    1379      * Escapes an identifier for a MySQL database (e.g. table/field names).
     1386     * Escapes an identifier for a MySQL database, e.g. table/field names.
    13801387     *
    13811388     * @since 6.1.0
    13821389     *
    13831390     * @param string $identifier Identifier to escape.
    1384      * @return string Escaped Identifier
     1391     * @return string Escaped identifier.
    13851392     */
    13861393    public function escape_identifier( $identifier ) {
     
    13891396
    13901397    /**
    1391      * Escapes an identifier value.
    1392      *
    13931398     * Escapes an identifier value without adding the surrounding quotes.
    13941399     *
    1395      * - Permitted characters in quoted identifiers include the full Unicode Basic Multilingual Plane (BMP), except U+0000
    1396      * - To quote the identifier itself, then you need to double the character, e.g. `a``b`
    1397      *
    1398      * @link https://dev.mysql.com/doc/refman/8.0/en/identifiers.html
     1400     * - Permitted characters in quoted identifiers include the full Unicode
     1401     *   Basic Multilingual Plane (BMP), except U+0000.
     1402     * - To quote the identifier itself, you need to double the character, e.g. `a``b`.
     1403     *
    13991404     * @since 6.1.0
    14001405     * @access private
    14011406     *
     1407     * @link https://dev.mysql.com/doc/refman/8.0/en/identifiers.html
     1408     *
    14021409     * @param string $identifier Identifier to escape.
    1403      * @return string Escaped Identifier
     1410     * @return string Escaped identifier.
    14041411     */
    14051412    private function _escape_identifier_value( $identifier ) {
     
    14341441     * Examples:
    14351442     *
    1436      *     $wpdb->prepare( "SELECT * FROM `table` WHERE `column` = %s AND `field` = %d OR `other_field` LIKE %s", array( 'foo', 1337, '%bar' ) );
    1437      *     $wpdb->prepare( "SELECT DATE_FORMAT(`field`, '%%c') FROM `table` WHERE `column` = %s", 'foo' );
     1443     *     $wpdb->prepare(
     1444     *         "SELECT * FROM `table` WHERE `column` = %s AND `field` = %d OR `other_field` LIKE %s",
     1445     *         array( 'foo', 1337, '%bar' )
     1446     *     );
     1447     *
     1448     *     $wpdb->prepare(
     1449     *         "SELECT DATE_FORMAT(`field`, '%%c') FROM `table` WHERE `column` = %s",
     1450     *         'foo'
     1451     *     );
    14381452     *
    14391453     * @since 2.3.0
     
    14411455     *              by updating the function signature. The second parameter was changed
    14421456     *              from `$args` to `...$args`.
    1443      * @since 6.1.0 Added '%i' for Identifiers, e.g. table or field names.
    1444      *              Check support via `wpdb::has_cap( 'identifier_placeholders' )`
    1445      *              This preserves compatibility with sprinf, as the C version uses %d and $i
    1446      *              as a signed integer, whereas PHP only supports %d.
     1457     * @since 6.1.0 Added `%i` for identifiers, e.g. table or field names.
     1458     *              Check support via `wpdb::has_cap( 'identifier_placeholders' )`.
     1459     *              This preserves compatibility with sprintf(), as the C version uses
     1460     *              `%d` and `$i` as a signed integer, whereas PHP only supports `%d`.
    14471461     *
    14481462     * @link https://www.php.net/sprintf Description of syntax.
     
    14791493         * Specify the formatting allowed in a placeholder. The following are allowed:
    14801494         *
    1481          * - Sign specifier. eg, $+d
    1482          * - Numbered placeholders. eg, %1$s
    1483          * - Padding specifier, including custom padding characters. eg, %05s, %'#5s
    1484          * - Alignment specifier. eg, %05-s
    1485          * - Precision specifier. eg, %.2f
     1495         * - Sign specifier, e.g. $+d
     1496         * - Numbered placeholders, e.g. %1$s
     1497         * - Padding specifier, including custom padding characters, e.g. %05s, %'#5s
     1498         * - Alignment specifier, e.g. %05-s
     1499         * - Precision specifier, e.g. %.2f
    14861500         */
    14871501        $allowed_format = '(?:[1-9][0-9]*[$])?[-+0-9]*(?: |0|\'.)?[-+0-9]*(?:\.[0-9]+)?';
    14881502
    14891503        /*
    1490          * If a %s placeholder already has quotes around it, removing the existing quotes and re-inserting them
    1491          * ensures the quotes are consistent.
     1504         * If a %s placeholder already has quotes around it, removing the existing quotes
     1505         * and re-inserting them ensures the quotes are consistent.
    14921506         *
    1493          * For backward compatibility, this is only applied to %s, and not to placeholders like %1$s, which are frequently
    1494          * used in the middle of longer strings, or as table name placeholders.
     1507         * For backward compatibility, this is only applied to %s, and not to placeholders like %1$s,
     1508         * which are frequently used in the middle of longer strings, or as table name placeholders.
    14951509         */
    14961510        $query = str_replace( "'%s'", '%s', $query ); // Strip any existing single quotes.
    14971511        $query = str_replace( '"%s"', '%s', $query ); // Strip any existing double quotes.
    14981512
    1499         $query = preg_replace( "/%(?:%|$|(?!($allowed_format)?[sdfFi]))/", '%%\\1', $query ); // Escape any unescaped percents (i.e. anything unrecognised).
     1513        // Escape any unescaped percents (i.e. anything unrecognised).
     1514        $query = preg_replace( "/%(?:%|$|(?!($allowed_format)?[sdfFi]))/", '%%\\1', $query );
    15001515
    15011516        // Extract placeholders from the query.
     
    15031518
    15041519        $split_query_count = count( $split_query );
    1505         $placeholder_count = ( ( $split_query_count - 1 ) / 3 ); // Split always returns with 1 value before the first placeholder (even with $query = "%s"), then 3 additional values per placeholder.
    1506 
    1507         // If args were passed as an array (as in vsprintf), move them up.
     1520        /*
     1521         * Split always returns with 1 value before the first placeholder (even with $query = "%s"),
     1522         * then 3 additional values per placeholder.
     1523         */
     1524        $placeholder_count = ( ( $split_query_count - 1 ) / 3 );
     1525
     1526        // If args were passed as an array, as in vsprintf(), move them up.
    15081527        $passed_as_array = ( isset( $args[0] ) && is_array( $args[0] ) && 1 === count( $args ) );
    15091528        if ( $passed_as_array ) {
     
    15121531
    15131532        $new_query       = '';
    1514         $key             = 2; // keys 0 and 1 in $split_query contain values before the first placeholder.
     1533        $key             = 2; // Keys 0 and 1 in $split_query contain values before the first placeholder.
    15151534        $arg_id          = 0;
    15161535        $arg_identifiers = array();
    15171536        $arg_strings     = array();
     1537
    15181538        while ( $key < $split_query_count ) {
    15191539            $placeholder = $split_query[ $key ];
     
    15291549            if ( 'i' === $type ) {
    15301550                $placeholder = '`%' . $format . 's`';
    1531                 $argnum_pos  = strpos( $format, '$' ); // Using a simple strpos() due to previous checking (e.g. $allowed_format).
     1551                // Using a simple strpos() due to previous checking (e.g. $allowed_format).
     1552                $argnum_pos = strpos( $format, '$' );
     1553
    15321554                if ( false !== $argnum_pos ) {
    1533                     $arg_identifiers[] = ( intval( substr( $format, 0, $argnum_pos ) ) - 1 ); // sprintf argnum starts at 1, $arg_id from 0.
     1555                    // sprintf() argnum starts at 1, $arg_id from 0.
     1556                    $arg_identifiers[] = ( intval( substr( $format, 0, $argnum_pos ) ) - 1 );
    15341557                } else {
    15351558                    $arg_identifiers[] = $arg_id;
    15361559                }
    1537             } elseif ( 'd' !== $type && 'F' !== $type ) { // i.e. ('s' === $type), where 'd' and 'F' keeps $placeholder unchanged, and we ensure string escaping is used as a safe default (e.g. even if 'x').
     1560            } elseif ( 'd' !== $type && 'F' !== $type ) {
     1561                /*
     1562                 * i.e. ( 's' === $type ), where 'd' and 'F' keeps $placeholder unchanged,
     1563                 * and we ensure string escaping is used as a safe default (e.g. even if 'x').
     1564                 */
    15381565                $argnum_pos = strpos( $format, '$' );
     1566
    15391567                if ( false !== $argnum_pos ) {
    15401568                    $arg_strings[] = ( intval( substr( $format, 0, $argnum_pos ) ) - 1 );
    15411569                }
    1542                 if ( true !== $this->allow_unsafe_unquoted_parameters || '' === $format ) { // Unquoted strings for backwards compatibility (dangerous).
     1570
     1571                // Unquoted strings for backward compatibility (dangerous).
     1572                if ( true !== $this->allow_unsafe_unquoted_parameters || '' === $format ) {
    15431573                    $placeholder = "'%" . $format . "s'";
    15441574                }
    15451575            }
    15461576
    1547             $new_query .= $split_query[ $key - 2 ] . $split_query[ $key - 1 ] . $placeholder; // Glue (-2), any leading characters (-1), then the new $placeholder.
     1577            // Glue (-2), any leading characters (-1), then the new $placeholder.
     1578            $new_query .= $split_query[ $key - 2 ] . $split_query[ $key - 1 ] . $placeholder;
    15481579
    15491580            $key += 3;
    15501581            $arg_id++;
    15511582        }
    1552         $query = $new_query . $split_query[ $key - 2 ]; // Replace $query; and add remaining $query characters, or index 0 if there were no placeholders.
     1583
     1584        // Replace $query; and add remaining $query characters, or index 0 if there were no placeholders.
     1585        $query = $new_query . $split_query[ $key - 2 ];
    15531586
    15541587        $dual_use = array_intersect( $arg_identifiers, $arg_strings );
     1588
    15551589        if ( count( $dual_use ) ) {
    15561590            wp_load_translations_early();
     
    15721606        if ( $args_count !== $placeholder_count ) {
    15731607            if ( 1 === $placeholder_count && $passed_as_array ) {
    1574                 // If the passed query only expected one argument, but the wrong number of arguments were sent as an array, bail.
     1608                /*
     1609                 * If the passed query only expected one argument,
     1610                 * but the wrong number of arguments was sent as an array, bail.
     1611                 */
    15751612                wp_load_translations_early();
    15761613                _doing_it_wrong(
     
    15831620            } else {
    15841621                /*
    1585                  * If we don't have the right number of placeholders, but they were passed as individual arguments,
     1622                 * If we don't have the right number of placeholders,
     1623                 * but they were passed as individual arguments,
    15861624                 * or we were expecting multiple arguments in an array, throw a warning.
    15871625                 */
     
    16041642                if ( $args_count < $placeholder_count ) {
    16051643                    $max_numbered_placeholder = 0;
     1644
    16061645                    for ( $i = 2, $l = $split_query_count; $i < $l; $i += 3 ) {
    1607                         $argnum = intval( substr( $split_query[ $i ], 1 ) ); // Assume a leading number is for a numbered placeholder, e.g. '%3$s'.
     1646                        // Assume a leading number is for a numbered placeholder, e.g. '%3$s'.
     1647                        $argnum = intval( substr( $split_query[ $i ], 1 ) );
     1648
    16081649                        if ( $max_numbered_placeholder < $argnum ) {
    16091650                            $max_numbered_placeholder = $argnum;
    16101651                        }
    16111652                    }
     1653
    16121654                    if ( ! $max_numbered_placeholder || $args_count < $max_numbered_placeholder ) {
    16131655                        return '';
     
    16361678                        '4.8.2'
    16371679                    );
    1638                     $value = ''; // Preserving old behaviour, where values are escaped as strings.
    1639                 }
     1680
     1681                    // Preserving old behavior, where values are escaped as strings.
     1682                    $value = '';
     1683                }
     1684
    16401685                $args_escaped[] = $this->_real_escape( $value );
    16411686            }
     
    38733918
    38743919    /**
    3875      * Determine DB or WPDB support for a particular feature.
    3876      *
    3877      * Capability sniffs for the database server and current version of wpdb.
    3878      *
    3879      * Database sniffs test based on the version of MySQL the site is using.
     3920     * Determines whether the database or WPDB supports a particular feature.
     3921     *
     3922     * Capability sniffs for the database server and current version of WPDB.
     3923     *
     3924     * Database sniffs are based on the version of MySQL the site is using.
    38803925     *
    38813926     * WPDB sniffs are added as new features are introduced to allow theme and plugin
     
    39273972            case 'utf8mb4_520': // @since 4.6.0
    39283973                return version_compare( $version, '5.6', '>=' );
    3929             case 'identifier_placeholders': // @since 6.1.0, wpdb::prepare() supports identifiers via '%i' - e.g. table/field names.
     3974            case 'identifier_placeholders': // @since 6.1.0
     3975                /*
     3976                 * As of WordPress 6.1, wpdb::prepare() supports identifiers via '%i',
     3977                 * e.g. table/field names.
     3978                 */
    39303979                return true;
    39313980        }
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