This now has no consumers in the tree, and for a very long time PHP has had its one feature built-in: http://php.net/manual/en/filter.examples.validation.php
commit eaad6aa98d0cf904d83f0f3d3ef6911af098a983 Author: Michael Orlitzky <mjo@gentoo.org> Date: Tue Mar 14 11:29:06 2017 -0400 dev-php/PEAR-Net_CheckIP: remove masked package. Gentoo-Bug: 609128