Requests_SSL::verify_reference_name( string $reference )

Verify that a reference name is valid


Verifies a dNSName for HTTPS usage, (almost) as per Firefox’s rules:

  • Wildcards can only occur in a name with more than 3 components
  • Wildcards can only occur as the last character in the first component
  • Wildcards may be preceded by additional characters

We modify these rules to be a bit stricter and only allow the wildcard character to be the full first component; that is, with the exclusion of the third rule.



(string) (Required) Reference dNSName


(boolean) Is the name valid?


File: wp-includes/Requests/SSL.php

	public static function verify_reference_name($reference) {
		$parts = explode('.', $reference);

		// Check the first part of the name
		$first = array_shift($parts);

		if (strpos($first, '*') !== false) {
			// Check that the wildcard is the full part
			if ($first !== '*') {
				return false;

			// Check that we have at least 3 components (including first)
			if (count($parts) < 2) {
				return false;

		// Check the remaining parts
		foreach ($parts as $part) {
			if (strpos($part, '*') !== false) {
				return false;

		// Nothing found, verified!
		return true;