- if ( self::isIPv4( $ip ) || !self::isIPv6( $ip ) ) {
- return $ip; // nothing else to do for IPv4 addresses or invalid ones
+ /* If not an IP, just return trimmed value, since sanitizeIP() is called
+ * in a number of contexts where usernames are supplied as input.
+ */
+ if ( !self::isIPAddress( $ip ) ) {
+ return $ip;
+ }
+ if ( self::isIPv4( $ip ) ) {
+ // Remove leading 0's from octet representation of IPv4 address
+ $ip = preg_replace( '/(?:^|(?<=\.))0+(?=[1-9]|0\.|0$)/', '', $ip );
+ return $ip;