wp_kses_bad_protocol( string $string, string[] $allowed_protocols )

Sanitizes a string and removed disallowed URL protocols.

Description

This function removes all non-allowed protocols from the beginning of the string. It ignores whitespace and the case of the letters, and it does understand HTML entities. It does its work recursively, so it won’t be fooled by a string like javascript:javascript:alert(57).

Parameters

$string

(string) (Required) Content to filter bad protocols from.

$allowed_protocols

(string[]) (Required) Array of allowed URL protocols.

Return

(string) Filtered content.

Source

File: wp-includes/kses.php

function wp_kses_bad_protocol( $string, $allowed_protocols ) {
	$string     = wp_kses_no_null( $string );
	$iterations = 0;

	do {
		$original_string = $string;
		$string          = wp_kses_bad_protocol_once( $string, $allowed_protocols );
	} while ( $original_string != $string && ++$iterations < 6 );

	if ( $original_string != $string ) {
		return '';
	}

	return $string;
}

Changelog

Version Description
1.0.0 Introduced.

© 2003–2021 WordPress Foundation
Licensed under the GNU GPLv2+ License.
https://developer.wordpress.org/reference/functions/wp_kses_bad_protocol