Summery Summery
Verify the certificate against common name and subject alternative names
Syntax Syntax
Description Description
Unfortunately, PHP doesn’t check the certificate against the alternative names, leading things like ‘https://www.github.com/‘ to be invalid. Instead
Parameters Parameters
- $host
-
(Required) Host name to verify against
- $cert
-
(Required) Certificate data from openssl_x509_parse()
Return Return
(bool)
Source Source
File: wp-includes/Requests/SSL.php
public static function verify_certificate($host, $cert) { // Calculate the valid wildcard match if the host is not an IP address $parts = explode('.', $host); if (ip2long($host) === false) { $parts[0] = '*'; } $wildcard = implode('.', $parts); $has_dns_alt = false; // Check the subjectAltName if (!empty($cert['extensions']) && !empty($cert['extensions']['subjectAltName'])) { $altnames = explode(',', $cert['extensions']['subjectAltName']); foreach ($altnames as $altname) { $altname = trim($altname); if (strpos($altname, 'DNS:') !== 0) { continue; } $has_dns_alt = true; // Strip the 'DNS:' prefix and trim whitespace $altname = trim(substr($altname, 4)); // Check for a match if (self::match_domain($host, $altname) === true) { return true; } } } // Fall back to checking the common name if we didn't get any dNSName // alt names, as per RFC2818 if (!$has_dns_alt && !empty($cert['subject']['CN'])) { // Check for a match if (self::match_domain($host, $cert['subject']['CN']) === true) { return true; } } return false; }
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See also See also
- https://tools.ietf.org/html/rfc2818#section-3.1: RFC2818, Section 3.1